Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Try these steps in order:
- Start Outlook in safe mode to check whether an add-in is causing the crash.
- Press Windows key + R.
- Type
Outlook /safeand select OK. - In Choose Profiles, accept the default profile and select OK.
- If Outlook opens in safe mode, the issue is likely caused by an add-in.
- Disable Outlook add-ins if safe mode works.
- In Outlook, go to File > Options > Add-ins.
- At the bottom, make sure Manage shows COM Add-ins, then select Go.
- Clear all selected add-ins, then select OK.
- Restart Outlook normally.
- If Outlook starts, re-enable add-ins one at a time until the problem add-in is identified.
- Repair the Office installation.
- Close all Office apps.
- Open Control Panel > Programs and Features.
- Right-click Microsoft Office 2016, Microsoft Office 2013, or Microsoft Office 2010, then select Repair.
- If the built-in Repair now button in the error dialog does not help, repairing from Windows is the next step.
- Create a new Outlook profile if Outlook still does not start.
- A corrupted Outlook profile can prevent Outlook from opening.
- Create a new profile by following Create an Outlook profile.
- Then restart Outlook and select the new profile in the Choose Profile dialog.
- If Outlook opens normally, the original profile was corrupted.
- Repair Outlook data files.
- Exit Outlook.
- Run the Inbox Repair Tool (
scanpst.exe) and follow the steps in Repair Outlook Data Files (.pst and .ost).
- If Outlook freezes or still does not respond, repair the AppData registry path and then repair Office again.
- Warning: editing the registry incorrectly can cause system problems.
- Open Registry Editor.
- Go to:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders - Double-click AppData.
- Set Value data to
%USERPROFILE%\AppData\Roaming - Select OK, exit Registry Editor, and then run Office Repair again.
- Check antivirus software.
- Make sure antivirus definitions are up to date.
- Outdated or conflicting antivirus software can prevent Outlook from working correctly.
If the same error appears in Word, Excel, and Outlook, focus first on the Office repair step because the issue may affect the full Office installation.
References