Business Central Payables Agent Known Senders: Email Review Policies, Security and Copilot Credits

Rolled out beginning with the August 2026 minor release of 2026 release wave 1 (reaching general availability on August 7, 2026, for Business Central on the web across Worldwide standard multi-tenant cloud instances), this update overhauls how the Payables Agent decides whether an incoming PDF invoice email needs human intervention before processing begins. Instead of treating a trusted, ten-year supplier the exact same way as an unrecognized cold-emailer, Business Central now allows teams to maintain a dynamic Known Senders list with per-sender governance policies.

Here is a complete breakdown of how the new email review policies work, the exact order of operations the agent uses to evaluate incoming messages, and what Business Central administrators need to know about permissions, shared mailboxes, and Copilot credit consumption before flipping the switch.

The Problem with "All-or-Nothing" Inbox Automation​

To appreciate why this update matters, it helps to look at how the Payables Agent operates under the hood. In Dynamics 365 Business Central online, the Payables Agent monitors a designated Microsoft 365 mailbox (either a user mailbox or, as Microsoft recommends, a dedicated shared mailbox) for incoming vendor invoices sent as PDF attachments. When an invoice lands, the agent reads the document, matches vendor and account details against historical patterns or purchase orders, and prepares a purchase invoice draft.

Previously, organizations faced a binary bottleneck:

• Supervisor approval on every email: Every single incoming message required a human to approve the email task before the agent would touch the attachment—creating repetitive friction when dozens of recurring invoices arrived from the same reliable vendors.
• Turning email review off entirely: Disabling email review removed the bottleneck, but it also meant the agent would blindly attempt to process whatever landed in the monitored inbox without sender-level filtering.

Why force an accounts payable specialist to click "approve" for the fiftieth time on a monthly utility or freight vendor they already trust? By introducing sender-specific review policies, Business Central lets organizations bypass repetitive email-level sign-offs for vetted suppliers while keeping a strict human gate in front of unknown or unverified sources.

Section Summary​

• The Core Issue: Prior to this update, Payables Agent email review was effectively an all-or-nothing toggle, forcing manual approval on trusted repeat vendors unless review was completely disabled.
• The Release: Tracked under Roadmap ID 576777, the Known Senders feature reached general availability in August 2026 (2026 release wave 1) for Dynamics 365 Business Central online.

Inside the New Email Review Modes and Evaluation Hierarchy​

According to Microsoft Learn's release plan and current Payables Agent setup documentation, administrators now configure a dedicated Email review setting on the Configure Payables Agent page. To ensure administrators make a deliberate governance choice rather than coasting on risky defaults, Microsoft's release notes emphasize that no default option is preselected when setting up inbox monitoring—an administrator must explicitly pick a policy before monitoring begins.

(Note for administrators comparing documentation: While Microsoft's initial 2026 wave 1 release plan referred to the recommended middle-ground option as Only if untrusted (recommended), the live Business Central product documentation labels this setting Manage per sender (recommended). Both refer to the same sender-aware operating mode.)

The 4-Step Evaluation Order Under "Manage Per Sender"​

When an administrator selects Manage per sender, the Payables Agent does not just check the sender list in a vacuum. According to Microsoft Learn's feature specifications and setup documentation, the agent evaluates incoming invoices in a strict priority order:

1. Manually Uploaded Invoices (Not Received via Email): If a user uploads a PDF invoice directly into the agent rather than receiving it through the monitored inbox, no email review is required.
2. Configured Email Subfolder: If an administrator specifies a particular mailbox subfolder in the agent's Folder field, all emails inside that monitored subfolder are treated as trusted and processed automatically without review. In fact, Microsoft Learn's Known Senders documentation explicitly notes that per-sender review policies are only applied when Manage per sender is selected and no monitored subfolder is configured.
3. Sender is on the Known Senders List: If the whole mailbox is monitored under Manage per sender and the sender's email address matches an entry on the Known Senders list, the agent follows that sender's assigned policy:
   • Approve: The agent processes the email and its invoice attachment automatically without requesting human review.
   • Ask: The agent pauses and requests human review before processing emails from this address.
   • Reject: The agent blocks/skips emails from this sender and does not create an agent task.
4. Authenticated Internal Senders (Same Organization): If the sender is internal to the same organization and not listed on the Known Senders list, no review is required. Microsoft's release plan notes that internal detection relies on email authentication headers (with full header-based internal detection slated in the roadmap for 2026 release wave 2, version 29.0). All other unrecognized external senders require human review before processing.

How the Known Senders List Builds Itself Organically​

One of the smartest design touches here is that administrators do not have to spend an afternoon importing CSV files of vendor email addresses before turning the feature on. While you can pre-populate the list manually, the Payables Agent builds the Known Senders list organically during daily operations.

According to Microsoft Learn's Manage known senders for Payables Agent documentation, when the agent creates a purchase invoice draft from a new sender, it adds that sender's email address to the Known Senders list before finalizing the invoice. When Manage per sender is active, the first email from an unknown address triggers a human review task. Once a reviewer approves that task and chooses to continue, the agent automatically assigns the Approve policy to that sender so subsequent invoices from that address sail through without manual email review. Furthermore, security telemetry is logged for every automatic addition to the list, giving audit-minded IT teams visibility into how trust was established.

Section Summary​

• Three Global Modes: Admins must actively choose between Always, Never, and Manage per sender (recommended).
• The Subfolder Caveat: Configuring the agent to monitor a specific mailbox subfolder overrides per-sender review policies and treats all emails in that folder as trusted.
• Organic Learning: Approving a first-time email task under Manage per sender automatically adds the sender with an Approve policy and logs security telemetry.

Step-by-Step Guide: Configuring Email Review and Managing Known Senders​

If your organization is running Dynamics 365 Business Central online with the Payables Agent enabled, here is how to access, pre-configure, and maintain your Known Senders policies based on Microsoft Learn's administrative guides.

Prerequisites and Permissions Check​

Before diving into the menus, make sure your account and environment meet Microsoft's baseline requirements:

• Agent Configuration Permissions: Your Business Central user account must either be listed in the agent's user access list with the Can Configure checkbox selected, or hold the Configure All Agents system permission (ID 9665, which is included in the SECURITY permission set). Working with routine agent tasks in the Copilot pane requires the Manage Agent Tasks permission (ID 9670).
• Exchange Mailbox Delegation: Unless you are monitoring your own personal mailbox, the user activating and configuring the agent needs Read and manage (Full Access) permissions on the Microsoft 365 shared mailbox. Keep in mind that Exchange permission propagation can take a few hours to take effect.
• Supported Locales: Microsoft notes that the Payables Agent is validated and supported in English (EN) across four specific locales: United States (US), United Kingdom (UK), Australia (AU), and New Zealand (NZ).

How to Access and Update the Known Senders List​

1. Open the Configuration Page: In the navigation bar at the upper right of the Business Central role center, select Payables Agent > Configure Payables Agent.
2. Locate Email Review Settings: Navigate to the Document processing card / Email review section and ensure your policy is set to Manage per sender (recommended) (and verify that no monitored subfolder is overriding it if you want per-sender rules to apply).
3. Open the Known Senders Page: Select Manage known senders. This opens the Payables Agent Known Senders page displaying all recorded email addresses and their current policies.
4. Pre-Configure a Vendor Manually:
   • Select New on the Payables Agent Known Senders page.
   • Enter the vendor's address in the Email field.
   • In the Review policy column, choose Approve, Ask, or Reject.
   • Select Close when finished.
5. Modify or Delete Existing Senders:
   • To change how an existing sender is handled, locate the address on the Payables Agent Known Senders page, change the Review policy column to Ask, Approve, or Reject, and select Update.
   • To remove an obsolete entry, select the sender and choose Delete. Note that if you delete a sender and they email another invoice later, the agent will simply treat them as a brand-new sender and add them back to the list using the default policy for your active email review setting.

Section Summary​

• Navigation Path: Manage policies via Payables Agent > Configure Payables Agent > Email review > Manage known senders.
• Proactive Control: Admins can manually add trusted vendors as Approve or known spam/test accounts as Reject before an email ever arrives.

Critical Analysis: Security Realities, Subfolder Trade-Offs, and AI Credit Costs​

From an enterprise IT and financial controls standpoint, the Known Senders list is a welcome maturity upgrade for Business Central's agentic workflows. However, based on general industry knowledge of email security and the specific mechanics documented by Microsoft, administrators need to watch out for three operational gotchas.

1. Email Review Approval Does Not Equal Final Invoice Posting​

First, let's clear up a common misconception: setting a vendor to Approve on the Known Senders list does not mean the AI agent is autonomously cutting checks or posting final ledgers without oversight. The Email review policy strictly governs whether a human must approve the incoming email before the agent begins processing the PDF into a purchase document draft. Furthermore, for organizations testing the waters in Business Central's 50-invoice free trial mode, Microsoft's setup documentation confirms that nothing is posted automatically—users still review drafts before finalization and review the resulting invoices before posting.

2. Multi-Company Subfolder Routing Disables Per-Sender Granularity​

Here is an architectural catch that multi-entity Business Central admins need to plan around. Each Business Central company can have only one Payables Agent. To save licensing overhead, Microsoft's setup guide suggests that organizations with multiple Business Central companies can share a single Microsoft 365 mailbox by creating Outlook rules that route invoices into company-specific subfolders, and then pointing each company's Payables Agent at its respective Folder.

That is a neat trick for mailbox consolidation, but remember the evaluation hierarchy: if a monitored subfolder is configured, the agent processes all emails in that folder automatically without review, bypassing the Known Senders list and the Email review setting entirely. If you rely on subfolder routing for a multi-company shared mailbox, your Exchange and Outlook rules become your only gatekeeper. If you want per-sender Ask, Approve, and Reject policies in a multi-company environment, you will need to provision separate dedicated shared mailboxes for each company rather than relying on monitored subfolders.

3. The "Reject" Policy as a Copilot Credit Saver​

Why should an administrator care about manually setting nuisance senders or test accounts to Reject? Beyond keeping the accounts payable task pane clean, it comes down to consumption-based billing.

While standard Copilot chat features in Business Central online are included with user licenses, autonomous agents consume Microsoft Copilot Credits (Copilot Studio messages) once a production environment moves past its initial 50-invoice free trial. When an agent is set to Reject a known unwanted sender—such as a marketing newsletter, an automated billing notification with non-invoice PDFs, or an internal test account—the agent skips the email entirely and creates no task. Actively curating the Reject policy and clearing stale unread emails before reactivating an agent helps prevent junk attachments from burning through your organization's Copilot Credit quota.

Finally, IT administrators should remember that an email address on an allowlist is only as trustworthy as your upstream mail hygiene. While Microsoft notes that internal sender detection leverages email authentication headers, external sender matching on the Known Senders list should always be paired with robust Exchange Online Protection (EOP) and Microsoft Defender for Office 365 anti-spoofing policies (SPF, DKIM, and DMARC enforcement) on the monitored shared mailbox.

Section Summary​

• Drafts vs. Posting: Approving a sender automates email intake and draft creation, not final general ledger posting.
• Multi-Company Dilemma: Sharing one mailbox across multiple Business Central companies via monitored subfolders disables Known Senders policies for those folders; use dedicated shared mailboxes per company if you need per-sender filtering.
• Cost Control: Using the Reject policy stops the agent from creating tasks for unwanted senders, helping conserve billable Copilot Credits after the 50-invoice free trial ends.