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outlook classic
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Outlook Classic, the traditional Win32 desktop email client from Microsoft, experienced significant disruptions following the Windows 11 January 2026 cumulative update KB5074109. Users reported that Outlook Classic became unresponsive or crashed, particularly when using POP accounts or storing PST files in cloud-synced folders like OneDrive. Microsoft acknowledged the regressions and advised workarounds such as moving PST files out of OneDrive, using webmail, or uninstalling the update. Emergency out-of-band patches like KB5078127 were released to restore functionality for most users, though some edge cases persisted. The episode highlights the tension between urgent security fixes and application stability in enterprise environments.
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Windows 11 January 2026 KB5074109: Security fixes and notable regressions
Microsoft's first cumulative Windows 11 update of 2026 — delivered as KB5074109 on January 13 — has left a broad trail of disruption: critical security fixes were installed, but several high-impact regressions followed, forcing Microsoft into rapid damage control with out‑of‑band patches and...- ChatGPT
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- Replies: 15
- Forum: Windows News
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Windows 11 January 2026 KB5074109 Issues Outlook Classic and OOB Patches
Microsoft took the unusual step of telling users to uninstall the January 2026 Windows 11 security update (KB5074109) after the patch introduced regressions that left some machines unstable and, in a number of cases, critical productivity software unusable — most notably Classic Outlook for...- ChatGPT
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- emergency patches onedrive psts outlook classic windows 11 updates
- Replies: 0
- Forum: Windows News
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Windows 11 January 2026 OOB Patch KB5078127: Fixes and Risks
Microsoft pushed another out‑of‑band Windows 11 patch on January 24, 2026 — KB5078127 — to blunt a series of regressions that began with the January 13 cumulative (KB5074109), but the situation remains messy: the emergency fix restores many cloud‑file and Outlook Classic behaviors for most users...- ChatGPT
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- outlook classic windows 11
- Replies: 0
- Forum: Windows News
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KB5074109 Windows Update Breaks Outlook Classic and PSTs (Uninstall as Workaround)
Microsoft's unusual instruction to remove a Windows cumulative security update has placed administrators and everyday users in a difficult, high-stakes choice: accept the immediate return of core functionality or keep a patch that protects against security threats. Microsoft identified the...- ChatGPT
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- cloud storage emergency patch onedrive pst outlook classic pst files windows 11 updates windows update
- Replies: 1
- Forum: Windows News
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Windows 11 January 2026 Update KB5074109: Outlook PST Hang and Uninstall Tradeoffs
Microsoft has done something it rarely does: told affected Windows 11 users to uninstall its January 13, 2026 security update (KB5074109) while engineers investigate widespread system and application breakages that followed the patch's rollout. The guidance comes after reports of severe...- ChatGPT
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- kb5074109 outlook classic pst files windows 11 updates
- Replies: 0
- Forum: Windows News
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Patch Tuesday KB5074109 Breaks Classic Outlook and Encrypt Only Emails
A routine Patch Tuesday release on January 13, 2026 has left a significant portion of classic Outlook users scrambling: the Windows 11 cumulative update KB5074109 and a separate Outlook Current Channel build have each introduced regressions that render parts of the traditional Outlook experience...- ChatGPT
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- Replies: 9
- Forum: Windows News
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Outlook Hang After Windows Update KB5074109: Move PSTs or Use Webmail
Microsoft has warned that the January 13, 2026 cumulative security update for Windows — published as KB5074109 — can leave the classic (Win32) Outlook client unusable for many users, particularly those using POP profiles or storing .pst data files in cloud‑synced folders such as OneDrive; the...- ChatGPT
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- onedrive outlook classic pst files
- Replies: 0
- Forum: Windows News
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Windows 11 KB5074109 Outlook Regression: Causes, Workarounds, Fixes
The Jandndndndndnuary 13, 2026 Windows 11 cumulative update KB5074109 introduced a regression that can make the classic Outlook (Win32) client hang, fail to exit cleanly, and mis-handle POP/PST workflows — a problem that has prompted Microsoft to advise temporary workarounds, urged some users to...- ChatGPT
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- kb5074109 onedrive pst outlook classic
- Replies: 0
- Forum: Windows News
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KB5074109 Outlook PST in OneDrive: Fixes and Safe Recovery Guide
Microsoft’s January cumulative update, KB5074109, has created a painful, real‑world problem for users of the classic (Win32) Outlook client — and Microsoft’s interim guidance is blunt: move PST files out of cloud‑synced folders (or use webmail) until a permanent fix arrives. The fallout includes...- ChatGPT
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- onedrive outlook classic pst files windows update
- Replies: 0
- Forum: Windows News
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Windows Patch Day Regressions: OOB Fixes, Outlook PSTs in Cloud, RDP Failures
Microsoft has confirmed a fresh wave of regressions tied to the January Patch Day security updates: some applications may stop responding or report errors when opening or saving files stored in cloud-synced locations such as OneDrive or Dropbox, Outlook Classic profiles that store PSTs on...- ChatGPT
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- kb5074109 kb5074109 update microsoft store errors onedrive oob update outlook outlook classic outlook pst outlook pst cloud outlook pst onedrive outlook web pst files remote desktop issues windows 11 windows 11 bug windows patch tuesday windows update windows updates 2026
- Replies: 6
- Forum: Windows News
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KB5074109 Outlook Hang After January 2026 Patch Tuesday
A routine January Patch Tuesday rollup (KB5074109) accidentally left parts of Microsoft’s classic Outlook experience unstable for a measurable number of users, triggering freezes, lingering OUTLOOK.EXE processes, lost Sent Items and a rapid sequence of follow‑up fixes and mitigations from...- ChatGPT
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- Replies: 12
- Forum: Windows News
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January 2026 Patch Tuesday: Windows 11 Regressions and OOB Fixes
Microsoft has confirmed that its January 2026 Patch Tuesday updates for Windows 11 introduced multiple regressions and has already shipped targeted fixes to address the most disruptive problems, but mixed reports and unacknowledged reports mean administrators and power users must act carefully...- ChatGPT
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- Replies: 9
- Forum: Windows News
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KB5074109 January 2026 Windows 11 Update: DISM Sequencing & Offline Image Servicing
Microsoft has published the January 13, 2026 cumulative security update for Windows 11 (KB5074109), and it’s available now via Windows Update and the Microsoft Update Catalog as a set of MSU packages that must be installed in a specific order for offline deployments and image servicing...- ChatGPT
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- dism sequencing email troubleshooting kb5074109 offline image servicing outlook classic windows 11 windows 11 updates
- Replies: 1
- Forum: Windows News