Outlook 365 for Mac refuses to quit

Hi @Adam Cohen, 

I hope you are doing well today. 

Based on your description, Outlook for Microsoft 365 for Mac in Legacy mode does not fully close when you choose Quit, and it quickly shows as running again in the Dock and Force Quit window. 

This behavior typically occurs because background processes or third party integrations are actively sending commands to the application. When a newly created profile is established, background database daemons can sometimes get stuck in a constant indexing loop. Consequently, the operating system forces the application to immediately relaunch to fulfill these ongoing background requests. 

Below are some workable options that might be the most appropriate for your current situation: 

1/ Confirm Spotlight and indexing are not keeping Outlook running 

• Restart the Mac, then open Outlook and allow a few minutes for sync and indexing to complete before attempting to quit again. 
• Check whether there are multiple Outlook applications installed on the Mac, such as one in Applications and another older copy elsewhere, and then keep only one installed copy to avoid competing Spotlight importers. 
• In macOS Spotlight privacy settings, temporarily exclude the main drive, restart the Mac, and then remove the exclusion so Spotlight rebuilds the index in a clean state. 
• After the index rebuild finishes, open Outlook again, wait for the mailbox to fully load, and then quit Outlook from the Outlook menu to confirm it fully disappears from the Dock and Force Quit list. 

2/ Rebuild the Outlook identity and set a clean default profile 

• Close Outlook, then open Outlook Profile Manager and confirm which profile is currently set as default. 
• Create a new profile, set it as the default, and then start Outlook using that new profile. 
• After Outlook opens, sign in, let the mailbox complete initial sync, and then quit Outlook from the Outlook menu to test normal shutdown behavior. 
• If the new profile quits normally, move any required data from the prior profile into the new one, and then keep only the profile you actively use to reduce background conflicts. 

3/ Kill the Microsoft Database Daemon 

Because you just built a new profile to fix your search/indexing issues, Microsoft's background sync engines have been working overtime. If the database daemon gets stuck in a loop trying to verify the new index, it will hold the main Outlook application hostage. 

• Open Activity Monitor (hit Command + Space and type Activity Monitor). 
• In the search bar at the top right, type Microsoft. 
• Look for processes like Microsoft Database Daemon, Microsoft Sync Services, or Microsoft AutoUpdate. 
• Highlight them, click the X button at the top of the window, and select Force Quit. 
• Try quitting Outlook again. 

4/ Clear the Saved Application State 

macOS might have cached a corrupted application state from right after your profile rebuild, trapping Outlook in a loop where it thinks it is permanently supposed to be running. 

• Open Finder. 
• Click Go in the top menu bar, hold down the Option key, and click Library (this reveals the hidden user library). 
• Navigate to the Saved Application State folder. 
• Locate the folder named com.microsoft.Outlook.savedState and drag it to the Trash. 
• Empty the Trash and restart your MacBook. 

5/ The Terminal "Nuke" 

If Outlook still refuses to stay dead and the Force Quit dialog keeps failing, you can use Terminal to forcefully sever all background processes tying it down. 

• Open Terminal (Command + Space -> Terminal). 
• Paste the following command and hit Return: killall -9 "Microsoft Outlook" 
• Immediately follow it with this command to kill the daemon: killall -9 "Microsoft Database Daemon" 

Once you forcefully break the cycle, Outlook should behave normally the next time you boot it up. 

If the behavior continues after reinstall, collect Outlook diagnostics from within the Outlook Help menu and share the incident details, since that gives Microsoft Support the background activity evidence needed to identify what is preventing Outlook from closing fully. 

I hope this information is helpful. Please follow these steps and let me know if it works for you. If you have any updates regarding the issue, please feel free to share them with me.          

Thank you for your patience and your understanding. I look forward to continuing the conversation. 

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Outlook for Mac profiles and the Spotlight index are tightly coupled. After recreating a profile to fix search, Outlook may still be holding background processes or a corrupted index/profile path can cause it to appear as if it never fully quits.

Use the following sequence to cleanly reset the search index for the new profile and, if needed, repair the profile itself. This both addresses search issues and can stop Outlook from hanging in a half-closed state.

1. Restart macOS
   • Restart the Mac to ensure all Outlook and Spotlight services are fully stopped.
2. Verify the Outlook Spotlight importer
   • Open Finder > Applications > Utilities > Terminal.
   • Run:

          mdimport -L
     

   • If more than one instance of Microsoft Outlook Spotlight Importer.mdimporter appears, delete the Outlook application that is not being used, empty it from the Trash, restart the Mac again, and repeat this step until only one importer remains.
3. Manually reindex Outlook for the current profile
   • In Terminal, run the mdimport command against the current Outlook profile, substituting the actual macOS user name and Outlook profile name (for example, Main Profile):

          mdimport -g "/Applications/Microsoft Outlook.app/Contents/Library/Spotlight/Microsoft Outlook Spotlight Importer.mdimporter" -d1 "/Users/<user_name>/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/<my_profile_name>"
     

   • The path after -g is the default Outlook installation path.
   • The path after -d1 is the default profile path; <my_profile_name> is Main Profile by default unless renamed.
   • Allow time for reindexing to complete; this can take a while depending on mailbox size.
4. Restart Outlook and test quitting
   • After reindexing completes, start Outlook, let it fully load and finish any background sync/index activity, then choose Outlook > Quit Outlook.
   • Confirm whether the dock indicator disappears and Outlook no longer appears in Force Quit Applications.
5. If the issue persists, rebuild or replace the profile
   • Use Outlook Profile Manager to manage profiles:
     1. In Finder, open Applications.
     2. Ctrl+click Microsoft Outlook and select Show Package Contents.
     3. Open Contents > SharedSupport, then launch Outlook Profile Manager.
     4. Create a new profile and set it as default, or delete and recreate the problematic profile.
   • Restart Outlook with the new/default profile and test quitting again.
6. If Outlook still refuses to quit
   • After the above steps and sufficient time for Spotlight indexing, completely uninstall and reinstall Office for Mac, then recreate the Outlook profile and test again.

These steps address both corrupted Spotlight index issues and profile corruption that can keep Outlook processes from terminating cleanly.

References:

• Troubleshoot search issues in Outlook for Mac
• Outlook for Mac search returns "No Results," and task items are not displayed
• Manage profiles or identities in Outlook for Mac