Hi Astrid,
Based on your description, you are unable to delete emails in the IMAP mailbox, to better understand your issue, I need to confirm a few details:
- What detailed version of Outlook are you using?
- Did you encounter some error message?
Given this situation, you can try the following general solutions to see if they resolve the issue:
- In the folder list, right-click the Deleted Items folder or the Trash folder, and then select Empty Folder. Restart Outlook and try again.
- Try to delete these messages again by pressing the Shift+Delete keys.
- Update or repair Office. Detailed steps can be found in Install Office updates (microsoft.com) and Repair an Office application (microsoft.com)
- You can try creating a new profile for your IMAP account in Outlook: Control Panel > Mail > Show Profiles, Add a new profile.
- Repair Outlook Data Files. Detailed steps can be found in Repair Outlook Data Files (.pst and .ost) (microsoft.com)
- Open Outlook in safe mode and try again. To open Outlook in safe mode, right-click the Start button, and click Run. Type Outlook.exe /safe and click OK.
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