Pending Send Dynamics 365

Hello @Downar, Michael

Based on the error and the Pending Send status that you shared, from my experience, this usually means the email was created in Dynamics 365 but never actually handed off to the mail system for delivery.

In most Dynamics 365 scenarios, the cause might be related to mailbox or email integration configuration. So you can go to Settings > Email Configuration > Mailboxes, then change the view to Active Mailboxes.

Open the affected user’s mailbox and verify:

• The mailbox is enabled for outgoing email
• The email address is approved
• The mailbox has been Tested & Enabled successfully
• The outgoing method is Server-side synchronization (or Email Router)

If any of the above is missing, approve/test/enable the mailbox again, once the mailbox is correctly configured, Dynamics 365 should start processing emails that are stuck in Pending Send.

A few additional things worth checking:

• If the mailbox email address is not approved by an admin, sending will be blocked entirely
• If server-side sync is configured but failing, the system may disable the mailbox automatically after repeated errors
• Try sending directly from Outlook using the same mailbox. If it fails there as well, it could indicate an Exchange-related issue (such as quota or permissions), so you may want to pay attention to any error messages in that step

Please note that Microsoft Dynamics 365 is currently not supported in the Microsoft Q&A forum. If you’d like more accurate and in-depth guidance for Dynamics 365, I recommend posting your question in the official Dynamics 365 Community. There, product experts and community members can provide more targeted assistance.

Hope this helps.

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