Symptoms
- Outlook shows a splash screen then closes
- Error message on launch
- Outlook freezes when opening a specific email
- Works in safe mode but not normally
Likely causes
- CommonCorrupted Outlook profileProfile data can become damaged after a crash or bad shutdown.
- CommonProblematic add-inThird-party add-ins load at startup and can conflict with Outlook.
- PossibleCorrupted local data file (PST/OST)A damaged local mail file can prevent Outlook from reading your mailbox.
- PossibleOutdated Office installationBugs in older versions can cause crashes that later updates fix.
- Less commonConflicting antivirus scanning email filesSome security software locks files Outlook needs to open.
What to do
- Restart your computer, since a stuck background process can block Outlook from opening.
- Hold Ctrl while launching Outlook, or run it with the /safe switch, to start in safe mode with add-ins disabled.
- If safe mode works, go to Outlook's add-in settings and disable add-ins one by one to find the cause.
- Run Office's built-in repair tool from your operating system's installed apps settings.
- Create a new Outlook profile and set up the account again if the old profile seems corrupted.
- Update Office to the latest version.
- Use Outlook's inbox repair tool (SCANPST) on the data file if a specific file seems damaged.
When to call a pro
If this is a work computer managed by IT, contact your IT department before making changes to Office.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.