Some common culprits include:
There are other issues, too, that can contribute.
Regardless of the specific cause, there are several key troubleshooting fixes to try that might help.
Open Outlook in Safe Mode.
Scan your system for malware.
If the software is damaged, use the built-in Microsoft 365 repair utility to fix it.
Repair your Outlook profile.
Outlook profiles can become corrupted, causing all sorts of problems, including Outlook not opening.
As you’re free to tell, this step is only useful if your problem is sporadic.
Repair your Outlook data files.
If Outlook still doesn’t open, use the Inbox Repair tool to find and possibly fix the problem.
This only works in Outlook 2016 and older.
If you’re not sure which version you have, go ahead and try these steps.
Reset the navigation pane.
A startup issue with the navigation pane can prevent some versions of Outlook from opening correctly.
it’s possible for you to do this through the Run dialog box.
If Outlook opens intermittently, seize the opportunity to check for updates viaHelp>Check for updates.
A recent update could include a fix for the problem.
Install any available updates you see.
Rebuild the Outlook database.
Back up any Outlook data stored only on your gear before you rebuild the database.
