Resolving DPI Scaling Issues in Windows Server 2022 via RDP & Horizon

Windows Server 2022 users managing Remote Desktop Services (RDS) environments have recently encountered a perplexing and disruptive issue involving DPI scaling when connecting via Remote Desktop Protocol (RDP) or VMware Horizon (recently rebranded as Omnissa). In certain scenarios, screens on Windows Server 2022 display incorrectly scaled user interface elements — either appearing excessively large or distinctly too small — severely impacting usability and productivity in virtual desktops and remote sessions.
This article delves into the specifics of the problem, the environmental context, investigative findings, and practical troubleshooting insights, alongside an exploration of broader implications for Windows RDS and remote display technologies in modern IT settings.

The Environment and Symptoms​

The issue emerged in environments running VMware Horizon 8 (now Omnissa) alongside Windows Server 2022 Datacenter edition with all the latest updates installed. Administrators noted that display scaling began malfunctioning unexpectedly a few weeks after deployment, with connections over both VMware Horizon and regular RDP affected. Depending on the client resolution, the entire remote desktop session would depict elements either way too large or too small, suggestive of Windows applying an incorrect DPI (Dots Per Inch) setting.
Key symptoms observed included:

• Incorrect scaling independent of connection method (Horizon or RDP).
• Overly large or small UI elements depending on resolution.
• Windows apparently ignoring the DPI scaling requested by the client device.
• The lock screen on the ESXi console showing incorrect scaling.
• Scaling incorrectness persisting despite reinstalling VMware Horizon Agent.
• Temporary resolution upon server restoration from backup, with scaling correct initially but deteriorating after days.
• Scaling stability when access limited exclusively to IT users, hinting that particular user behavior triggers the DPI override.

A registry comparison under HKCU\Control Panel\Desktop\WindowMetrics exposed a crucial clue: the problematic user profiles showed AppliedDPI set to 0x00000078 (120), implying 125% scaling, whereas correctly functioning profiles had AppliedDPI at 0x00000060 (96), which is 100% scaling. Attempts to delete local user profiles or reconfigure the Horizon Agent had no discernible impact. UI scaling settings in Windows did not report abnormalities, complicating diagnosis.

Investigative Insights​

This issue appears rooted in the Windows Registry setting for DPI rather than a Horizon client-side misconfiguration, as client logs confirmed the correct DPI request was sent but ignored. Windows Server 2022 seems to override the expected DPI value, defaulting instead to an unwanted 125% scaling (120 DPI) at the user profile level.
Two prominent factors contribute to this problem:

• User-Specific Registry Changes Affecting DPI
  The fact that limiting access to IT personnel prevents the issue strongly suggests that a specific user account or an inadvertent user action is modifying the AppliedDPI registry value. It might be due to profile corruption, a rogue script, or user settings saved unintentionally. These user-specific overrides gradually revert the registry setting from the working default (100%, 96 DPI) to 125% (120 DPI) scaling.
• Windows Server 2022 DPI Handling in Remote Sessions
  DPI scaling under RDP and VMware Horizon often behaves differently than local console sessions. Windows manages DPI through multiple layers—system settings, per-user registry keys, and remote session protocols. Recent updates or subtle bugs in Windows Server 2022 may cause the server to ignore the remotely requested DPI, applying its local default instead. Reinstalling the Horizon Agent did not fix the issue, which points to Windows internal DPI processing rather than the agent software itself being at fault.

Additionally, peculiarities arise because display scaling changes at the locked ESXi console also manifest, which normally shouldn’t be affected by user DPI settings. Once a user logs in interactively, the display scaling normalizes, reinforcing the notion that user session context governs these discrepancies.

Diagnostic and Troubleshooting Recommendations​

Given the complex interplay of remote desktop protocols, Windows DPI registry settings, and user profiles, a methodical approach is key:

Registry and User Profile Inspection​

• Regularly inspect or export the registry key HKCU\Control Panel\Desktop\WindowMetrics\AppliedDPI across all user profiles.
• Implement a logon script to enforce the AppliedDPI value at 96, effectively locking the scaling to 100% on login.
• Monitor user-specific registry changes to identify when and by whom the DPI value switches.
• Clear obsolete local profiles or recreate problematic user accounts to rule out profile corruption.

RDP and Horizon Settings Adjustments​

• Examine RDP connection properties, especially options related to DPI scaling. For example, the RDP setting "Override high DPI scaling behavior" can affect client scaling enforcement.
• Verify that Horizon client and agent versions are fully updated, since vendors continue to patch DPI-related bugs.
• Consider disabling DPI scaling override policies at the session level through Group Policy or local security policy settings.
• Experiment with Horizon’s DPI scaling compatibility settings, if available, to improve fidelity.

Group Policy and Session Policies​

• Deploy Group Policy Objects that prevent users from modifying display scaling settings.
• Lock down the relevant registry keys using security permissions or system configurations to prevent unauthorized changes.
• Test these policies with controlled user accounts before wide implementation.

Vendor Collaboration and Community Input​

• Engage VMware/Omnissa and Microsoft support to report logs and detailed findings. Since both the RDP client and Horizon agent report correct DPI requests, the issue is likely on Windows Server’s internal DPI handling.
• Leverage community feedback from forums such as Spiceworks, where other IT professionals may have developed workarounds or identified patch-related causes.
• Monitor Microsoft Windows Release Health Dashboards and VMware support bulletins for related patch announcements or documented bugs.

Log and Analyze System Events​

• Increase logging for remote desktop sessions to capture DPI-related settings adjustment events.
• Scrutinize Windows Event Viewer for display or user profile registry modification logs during affected session times.
• Identify patterns related to specific users, login times, or session types triggering the DPI reversion.

Broader Implications and Context​

DPI scaling fidelity remains a long-standing challenge in Windows remote desktop services. As organizations rely increasingly on virtual desktop infrastructure (VDI), blended environments involving VMware Horizon and native Windows RDP sessions face pressure for consistent UI scaling.
Windows desktop application developers have struggled historically with DPI-awareness, requiring API features such as EnableNonClientDpiScaling and mixed-mode DPI awareness contexts to handle per-monitor scaling gracefully. Server-side scaling anomalies add layers of complexity. Windows Server 2022, with its updated Remote Desktop infrastructure, appears susceptible to certain DPI override regressive behaviors—possibly introduced in recent feature or security updates.
Ensuring consistent DPI scaling across multi-user remote sessions also highlights the importance of robust user profile management. Profiles inadvertently saving inappropriate DPI settings affect all subsequent logins, and such details can silently propagate through system restorations or backups.
The ongoing resolution of such issues requires coordination between system administrators, application developers, and platform vendors. It also stresses the need for thorough update testing in controlled environments before deploying patches or features to live critical server infrastructures.

Temporary Workarounds​

While a permanent fix from Microsoft or VMware may be pending, administrators can employ these immediate measures:

• Restore affected servers from clean backups and restrict access until the root cause user or action is isolated.
• Enforce the AppliedDPI registry key’s value explicitly at user login through scripting.
• Lock down the display scaling options via Group Policies to prevent user-level overrides.
• Use controlled test user accounts to monitor behavior and identify triggers.
• Regularly audit and document DPI registry settings and Horizon/RDP logs to catch reversion patterns early.

Conclusion​

The Windows Server 2022 DPI scaling anomaly via RDP and VMware Horizon embodies the nuanced challenges IT professionals face managing modern remote desktop environments. A seemingly small registry key — AppliedDPI — holds disproportionate sway over user experience quality in RDS sessions. Its unanticipated alteration, possibly tied to user profiles or subtle Windows DPI processing bugs, wreaks havoc in robust server-hosted virtualization setups.
Administrators encountering this issue should adopt a systematic approach: analyze registry states, restrict user capability around DPI settings, scrutinize remote session configurations, and collaborate proactively with vendor support. The problem’s persistence despite conventional remedies like Horizon Agent reinstallations signals a deeper Windows DPI scaling intricacy that may necessitate future patches or architectural refinements.
For professionals entrusted with the reliability of enterprise Windows Server environments, understanding and managing DPI scaling intricacies is crucial. Balancing between user convenience, security, and technological constraints in remote desktop scenarios demands vigilance, tested workflows, and adaptive policies. And with the rapid evolution of remote work infrastructure, these scaling nuances will remain a field to watch closely.
By staying informed, methodical, and engaged with vendor and community developments, IT teams can navigate these DPI scaling “gotchas” effectively, preserving seamless user experiences in the ever-complex RDS landscape.

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This analysis draws upon detailed community reports and expert insights documented in the Spiceworks forum thread titled "Windows Server 2022 DPI scaling broken via RDP & VMware Horizon" and supplemented with technical evaluation from Windows DPI handling documentation and related community troubleshooting guides .

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Source: Windows Server 2022 – DPI / Scaling broken via RDP & VMware Horizon

Windows Server 2022 users running Remote Desktop Services (RDS) in virtualized environments such as VMware Horizon are encountering a perplexing issue related to DPI (dots per inch) display scaling. This widespread problem causes user interfaces to appear improperly sized—either excessively large or too small—when connecting remotely via RDP clients or VMware Horizon sessions. Consequently, this disrupts user experience significantly, as visual elements are either unusably magnified or diminished, complicating routine administrative and end-user tasks.

Nature of the DPI Scaling Issue in Windows Server 2022 RDS​

The issue manifests as inconsistent and incorrect DPI scaling behavior across sessions. Users connecting with either VMware Horizon (now rebranded as Omnissa) or standard Remote Desktop Protocol (RDP) clients find that display scaling no longer aligns with expectations based on their client devices’ native resolution and DPI settings. Instead of scaling being client-driven or adaptive, Windows Server 2022 appears to override the requested DPI settings and applies an incorrect scaling value.
In real-world scenarios, users have reported that after logging in, the session’s UI elements look either “way too large” or “way too small,” negatively impacting usability and productivity. This erratic scaling is not constant but tends to appear after a few days of operation, disappearing temporarily only when the server is restored from backup, suggesting some transient or user-triggered configuration changes affecting the DPI settings.

Investigation and Key Observations​

The critical clue lies within the Windows registry, specifically under the key:
HKCU\Control Panel\Desktop\WindowMetrics
On affected systems, the registry value AppliedDPI is often found set to 0x00000078 (decimal 120), equating to 125% scaling, whereas a properly functioning system uses the standard DPI value of 0x00000060 (decimal 96) for 100% scaling.
Efforts to isolate and resolve the problem have shown that:

• Restoring the system from backup resets the DPI scaling to the correct AppliedDPI = 96 setting temporarily.
• Restricting access to only IT department users prevents the issue from reoccurring, pointing to a user or group of users potentially triggering a scaling override.
• VMware Horizon logs indicate the client correctly requests the appropriate scaling factor, but the Windows server disregards this and applies its own DPI setting.
• Deleting all local user profiles does not solve the problem.
• Reinstalling the VMware Horizon Agent also yields no change.
• Even on the direct ESXi console (outside of any remote display session), the login lock screen appears overly scaled, but once logged in locally, the scaling is correct.
• Adjusting VM configuration such as vRAM does not impact this issue.
• Windows display settings themselves do not reveal unusual or altered scaling configurations.

This points to a complex interplay between user-specific settings, Windows DPI management in RDS environments, and possibly specific user actions or software interactions that alter the registry DPI values.

Understanding DPI and Registry Impact on Remote Sessions​

Windows manages DPI scaling information both globally and per-user, wherein the DPI value impacts the size of UI elements. In RDS and virtualization contexts, this is even more critical because sessions must adapt dynamically to the client's display scale factors to provide an optimal experience.
The DPI setting under HKCU\Control Panel\Desktop\WindowMetrics reflects the user’s applied DPI overrides. A systemic override at this level overrides client scaling preferences during remote sessions.
Several hypotheses arise from the data:

• User-Initiated Changes: Since limiting users avoids recurrence, it suggests that certain users unintentionally modify DPI settings during their sessions, affecting the registry values persistently.
• Windows or Application Bugs: Given Windows Server 2022’s continuous updates, a recent security patch or update could have introduced a regression impacting DPI scaling behavior in RDP and VMware Horizon sessions.
• Agent and Client Mismatch: The fact that reinstallation of the Horizon Agent does not fix the issue and yet client logs reflect correct scaling requests indicates the DPI enforcement may be happening on the Windows side, not the virtualization agent.

Troubleshooting and Mitigation Strategies​

Affected IT shops can follow a sequence of investigative and remedial actions:

• Registry Baseline Enforcement: Because restoring backups resets DPI values, administrators can export the correct registry settings and deploy login scripts or Group Policies to enforce AppliedDPI = 96 at user login, overriding any problematic changes.
• User Profile Audits: Identify and monitor users with recurring DPI setting changes by comparing their registry hives before and after login sessions.
• Group Policy Lockdown: Use Group Policies to restrict the ability of standard users to modify display scaling settings, potentially locking down visual registry keys to prevent corruption or unwanted changes.
• RDP Client and Horizon Settings Review: Adjust connection parameters such as “Override high DPI scaling behavior” in remote desktop clients. Though client requests appear correct, experimenting with these settings can sometimes force Windows to adhere to the client’s DPI preferences.
• Maintain Horizon Agent Updates: Keep Horizon agents up to date and coordinate with VMware/Omnissa support. Though immediate reinstallation didn’t help, future patches may address DPI handling nuances.
• Enhanced Logging and Auditing: Enable verbose logs and Windows Event Log auditing around display settings changes to detect triggers, accompanied by monitoring system and user event correlations.
• Testing Isolated User Accounts: Create controlled test accounts with enforced DPI settings to evaluate whether the problem persists under controlled conditions.

Broader Context: DPI Scaling Challenges in Remote Desktop Environments​

This issue is not isolated to this environment or Windows Server 2022. DPI scaling in RDS and virtualization often presents challenges, especially with mixed DPI settings across multiple client devices. Windows’ internal DPI awareness—introduced to accommodate modern high-resolution screens—can conflict with legacy apps or session management.
The DPI discrepancy can sometimes lead to distorted UI components, misaligned fonts, and windows of odd size, complicating usability.
Developers and administrators alike know that DPI settings are managed across a mix of capabilities:

• User-level DPI awareness manifests through registry keys.
• Application-level awareness (high DPI support flags, manifest files).
• System-level overrides applied transiently.
• Remote Desktop scaling negotiation protocols that exchange DPI scaling factors.

Windows Server’s handling of DPI scaling in virtualized RDS sessions occasionally diverges from local sessions, creating unpredictable behavior if registry values or policy enforcement diverge.

Implications and Operational Impact​

Such DPI scaling failures have measurable consequences:

• Productivity Loss: Overly large or small UI elements frustrate users, making it difficult to use business-critical applications.
• Support Burden: IT teams must spend time diagnosing elusive display issues, often involving complicated workarounds.
• Security Risks: User workarounds or policy relaxations to fix DPI issues might weaken security postures if unrestricted permissions are granted to end users.
• Vendor Dependencies: Reliance on virtualization vendors (like VMware Horizon/Omnissa) to patch or support DPI scaling behavior increases complexity.

Forward-Looking Perspectives​

Ongoing collaboration between Microsoft, VMware/Omnissa, and IT communities is essential to root cause and resolve DPI scaling inconsistencies. IT professionals are encouraged to:

• Participate actively in vendor support channels to escalate the issue.
• Share diagnostic data and environment details to accelerate awareness.
• Stay current on Windows Server 2022 cumulative updates, as future patches might fix underlying DPI scaling regressions.
• Monitor Windows and VMware forums for emerging best practices or official fixes.
• Consider leveraging newer features in Windows Server for per-monitor DPI awareness or alternate remote display protocols.

Conclusion​

The DPI scaling issues experienced in Windows Server 2022 Remote Desktop environments via VMware Horizon and RDP illustrate the complexities involved in delivering a seamless remote UI experience. The underlying problem links strongly to unexpected changes in user registry DPI settings (AppliedDPI) that override client scaling requests, causing inconsistent display sizes in sessions. While temporary restores and access restrictions offer short-term relief, administrators must develop systematic approaches involving registry monitoring, Group Policy enforcement, and collaboration with vendors for lasting remediation.
Given the critical role of remote desktop protocols in modern IT operations, resolving such display issues is paramount to maintaining productivity and user satisfaction in virtualized Windows server environments. Until vendors release permanent fixes, diligent monitoring, configuration lockdowns, and user education remain the best means to manage this vexing DPI scaling challenge.

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This analysis synthesizes user-reported evidence from Spiceworks community discussions and registry findings, augmented by common expert recommendations for RDS DPI issues in Windows Server 2022 and VMware Horizon environments.

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Source: Windows Server 2022 – DPI / Scaling broken via RDP & VMware Horizon

Windows Server 2022 has emerged as a robust platform for enterprise Remote Desktop Services (RDS) and virtual desktop infrastructure (VDI), especially when integrated with VMware Horizon (recently rebranded as Omnissa). However, a perplexing and disruptive issue has surfaced in some deployments related to DPI (dots per inch) scaling when using remote desktop connections. This technical quirk manifests as abnormal display scaling, where the graphical interface appears either excessively large or minuscule, undermining user experience and workflow on remote sessions.

The DPI Scaling Challenge in Windows Server 2022 RDS Environments​

The core symptom reported in affected environments is inconsistent and incorrect DPI scaling during remote connections—via both VMware Horizon and native Microsoft RDP clients. In practice, users notice that interface elements, icons, and text render at inappropriate sizes. Sometimes, the screen looks zoomed in excessively (e.g., scaled to 125%), while at other times, the scaling is too small (e.g., 100%). This fluctuation is not random but highly dependent on the resolution and DPI requested by the client device.
Central to the problem is Windows Server 2022's handling of DPI scaling parameters in remote sessions. Investigations have pinpointed an unusual override of the DPI scaling registry key:
HKCU\Control Panel\Desktop\WindowMetrics\AppliedDPI
In unaffected settings, this registry value is set to 0x00000060 (decimal 96), representing 100% scaling. However, problematic servers show a value of 0x00000078 (decimal 120), indicating 125% scaling. This value appears to be forcefully applied despite client requests to use different DPI settings, causing the display elements to render incorrectly.

Environment and Troubleshooting Steps​

The affected environments typically feature the latest versions of VMware Horizon (Omnissa) with Windows Server 2022 Datacenter hosts fully patched. The issue notably appears regardless of whether users connect via Horizon or traditional RDP, suggesting the root cause lies primarily in Windows rather than the connection brokers.
Administrators have attempted various remedial measures, including:

• Restoring servers from a known good backup, which temporarily resolves the scaling but with the issue recurring after some time.
• Limiting user access: When access is restricted exclusively to IT staff, the problem does not reappear, implying that particular user profiles or actions may trigger registry DPI overrides.
• Deleting local user profiles: This fails to correct the problem, indicating that DPI settings might be altered somewhere beyond immediate profile data.
• Reinstalling the VMware Horizon Agent: Removes the agent as a cause, reinforcing suspicion on Windows OS DPI processing.
• Modifying VM resources (e.g., vRAM): Shows no impact on DPI behavior.

An intriguing observation is that even the ESXi console lock screen displays excessive scaling, implying the glitch manifests at a system level, not just within user sessions.

Understanding the DPI Mechanism and Remote Desktop Impact​

Windows handles DPI scaling through a combination of client-side requests and server-side registry and session settings. In ideal conditions, the DPI scale factor requested by the client device (based on resolution and physical display size) should be honored by the server. However, with Windows Server 2022, there appears to be an override mechanism that enforces a fixed DPI scaling (125% in many scenarios), regardless of the client’s actual DPI request.
The challenge is compounded in RDS/VDI environments because the user interface must adapt seamlessly to diverse client devices connecting with various screen resolutions and DPI capabilities. Legacy DPI awareness models in Windows were insufficient for handling multiple clients with differing display characteristics.
With the introduction of per-monitor DPI awareness in Windows 8.1 and further refinements in Windows 10 and 11, Microsoft aimed to empower applications and system frameworks to dynamically adjust scaling per display. However, in server-based remote desktop contexts, some applications and the system default scaling settings do not fully support this flexibility, resulting in abrupt and incorrect DPI overrides.

Diagnosis: Is a User Setting or Windows Feature Responsible?​

Data and diagnostic efforts suggest the overriding AppliedDPI value could be influenced by:

• A specific user’s profile or session settings that inadvertently or unknowingly changes DPI scaling preferences.
• Background processes or group policies that enforce a default DPI setting on login.
• An elusive bug or regression in Windows Server 2022 DPI scaling implementation that misprocesses client DPI requests during session initialization.

Close scrutiny of registry keys across user profiles before and after connections point to persistent changes introduced by some session or user activity. Because restoring from backup temporarily resolves the problem—only for it to reoccur after non-IT users access the system—the issue hints at users altering DPI settings, perhaps unintentionally via display settings adjustments or remote control software.

Potential Solutions and Workarounds​

While a definitive patch or hotfix from Microsoft and VMware remains awaited, practical strategies for administrators include:

Registry Enforcement Scripts​

Creating logon scripts or scheduled tasks to check and reset the registry key AppliedDPI to 96 (100% scaling) can help restore a consistent scaling environment. This is a reactive solution but might standardize the user experience.

Group Policy Lockdowns​

Employing Group Policy Objects (GPOs) to restrict scaling changes at the user or computer level may prevent unauthorized or accidental DPI configuration alterations. Policies can be applied to disable user access to display scaling controls or lock registry settings corresponding to DPI.

RDP and Horizon Client Configuration​

Investigate and adjust the advanced settings in RDP clients and VMware Horizon configurations to:

• Enable or disable DPI syncing features.
• Override client DPI settings to enforce server-side scaling preferences.
• Ensure options like "Use all my monitors" and high-DPI optimization are appropriately set.

Administrators should test various combinations to discover which enforce the desired behavior without introducing additional display problems.

User Profile Hygiene​

Audit user profiles for display settings variations. If a particular user is found to trigger the problem, either retrain the user on correct settings or migrate affected users to a sanitized profile template.

Driver and Agent Updates​

Although reinstalling VMware Horizon Agent alone has shown no benefit, maintaining updated versions is advisable as vendors periodically address DPI compatibility issues and related bugs.

Broader Implications and Industry Insight​

This DPI scaling conundrum underscores key challenges faced in the modern remote desktop era. Remote work and virtualized desktops must cater to users joining from an ever-expanding variety of devices: laptops, tablets, smartphones, and multiple monitors of differing resolutions and DPI densities. The seamlessness of display scaling directly impacts productivity and user satisfaction.
Microsoft’s evolution from system-wide DPI settings to per-monitor DPI and mixed-mode awareness reflects a significant technical progression. However, server environments remain a complex use case, frequently relying on legacy components and processes that complicate full DPI compliance. Moreover, the interplay between client requests, group policies, remote desktop agents, and Windows internals adds layers of complexity.

Summary and Outlook​

Administrators operating Windows Server 2022 in conjunction with VMware Horizon are advised to monitor DPI scaling closely, especially following user logins and system updates. While registry overrides currently serve as both a symptom and a partial culprit, the root cause may lie in user behavior, system design, or a subtle bug in DPI handling during remote sessions.
Engagement with Microsoft and VMware support channels is essential to stay apprised of forthcoming fixes or configuration guidance. Meanwhile, practical mitigation via registry enforcement, GPOs, user training, and connection setting adjustments can maintain a usable remote desktop environment.
The message is clear: managing DPI scaling in virtualized RDS and VDI situations on modern Windows Server platforms is challenging but solvable with awareness, vigilance, and methodical troubleshooting.
By carefully balancing user needs, system controls, and vendor innovations, IT professionals can navigate the evolving landscape of remote desktop DPI scaling—ensuring crisp, clear, and correctly scaled displays in Windows Server 2022 RDS setups with VMware Horizon.

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This detailed examination amalgamates community reports, registry investigations, troubleshooting steps, and technical background to equip IT administrators with a comprehensive understanding of Windows Server 2022 DPI scaling issues over RDP and VMware Horizon connections.

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Source: Windows Server 2022 – DPI / Scaling broken via RDP & VMware Horizon