Outlook doesn't open

Try these in order:

1. End any stuck Outlook or Office processes.
   • Right-click the taskbar and open Task Manager.
   • Under Processes, look for Microsoft Outlook and any other Office processes.
   • Select each one and choose End task.
   • Then try opening Outlook again.
2. If new Outlook is the one hanging:
   • Right-click Start > Task Manager.
   • Select Microsoft Outlook > End task.
   • Reopen new Outlook.
   • If it still fails, uninstall and reinstall new Outlook for Windows from the Microsoft Store.
3. If classic Outlook is the one hanging, start it in safe mode to check add-ins.
   • Press Windows key + R.
   • Type outlook.exe /safe and select OK.
   • If prompted, accept the default profile and sign in.
   • If Outlook opens, go to File > Options > Add-ins.
   • Set Manage to COM Add-ins > Go.
   • Clear all add-in check boxes and select OK.
   • Restart Outlook normally.
   • If it works, re-enable add-ins one at a time, restarting Outlook after each one, until the problem returns. That identifies the faulty add-in.
4. Check whether Outlook is blocked by a hidden dialog box or a long-running action.
   • Press Alt+Tab and look for any Outlook confirmation window.
   • Also check the Outlook status bar to see whether it is processing a large move or delete operation.
5. Install the latest Windows and Microsoft 365 updates.
   • Outlook issues such as freezing and not responding can be resolved by current updates.
6. Repair Microsoft 365 / Office.
   • Close all Microsoft 365 apps.
   • Open Control Panel > Programs and Features.
   • Right-click the installed Microsoft Office entry and choose Change.
7. If classic Outlook still will not start, create a new Outlook profile.
   • A corrupted profile can prevent Outlook from opening.
   • After creating the new profile, restart Outlook and select that profile in Choose Profile.
   • Warning: if removing an old profile later, back up data files first. Removing a profile deletes offline cached content.
8. If classic Outlook opens but still behaves inconsistently, repair Outlook data files with scanpst.exe.
9. If the issue is specifically that Outlook will not reopen after closing or after sleep, and Task Manager shows Office processes still running, ending those processes can allow Outlook to open again.

• Outlook for Windows not responding, hangs, freezes, or stops working
• Classic Outlook not responding, stuck at "Processing," stopped working, or freezes
• I can’t start Microsoft Outlook or receive the error “Cannot start Microsoft Outlook. Cannot open the Outlook Window”
• Outlook won’t open or is stuck at loading profile