If you’re wondering how to stop Outlook from automatically closing, you’re definitely not alone. Many users face situations where Outlook shuts down unexpectedly, freezes, or disappears from the screen without warning. It’s frustrating, especially when you’re in the middle of reading or drafting an important email. When users ask why my Outlook is closing automatically or say they notice Outlook automatically closes after opening, the root causes can vary—from corrupted files to incompatible add-ins or outdated software.

This guide walks you through all the major reasons behind Outlook auto-closing and explains step-by-step methods to fix it. Each fix is beginner-friendly yet technically accurate so you can apply it easily. Apart from manual solutions, we also share the fantastic SysTools PST Repair Tool aka the best solution in the market.

Why Outlook Keeps Closing Automatically?

Before learning the fixes, it helps to understand what might be causing Outlook to crash or close without warning. Common reasons include:

  • Corrupted or oversized PST/OST files

  • Faulty or incompatible Outlook add-ins

  • Outdated Outlook or Windows patches

  • Corrupted Outlook profile

  • Conflicts with antivirus software

  • Damaged Office installation files

  • Low system resources or abrupt shutdowns

With these causes in mind, let’s jump into the methods that help you stop Outlook from shutting down unexpectedly.

1. Restart Outlook in Safe Mode

Safe Mode is one of the quickest ways to diagnose the issue. It helps identify whether add-ins or custom settings are behind the problem. If you want to stop Outlook from automatically closing, this is often the best starting point.

Steps:

  1. Press Windows + R.

  2. Type outlook.exe /safe and hit Enter.

  3. Check if Outlook runs smoothly without closing.

If Outlook stops crashing in Safe Mode, it’s likely that a faulty add-in is causing the trouble.

2. Disable Faulty Outlook Add-ins

Faulty or outdated add-ins are a common reason users ask why my Outlook is closing automatically. Add-ins can interfere with Outlook’s core processes and force it to shut down.

Steps:

  1. Open Outlook normally.

  2. Click File > Options > Add-ins.

  3. Select COM Add-ins from the dropdown and click Go.

  4. Uncheck all add-ins to disable them.

  5. Restart Outlook.

  6. Re-enable add-ins one at a time to find the problematic one.

If Outlook stabilizes after disabling an add-in, you’ve found the culprit.

3. Repair Outlook Data Files (PST/OST)

A corrupted PST/OST file is one of the top reasons behind Outlook closing by itself. If the data file is damaged, Outlook will struggle to load emails and eventually shut down.

Use ScanPST (Inbox Repair Tool):

  1. Close Outlook.

  2. Navigate to: C:\Program Files\Microsoft Office\root\OfficeXX\SCANPST.EXE

  3. Launch ScanPST.

  4. Select the PST file you want to repair.

  5. Click Start.

  6. After the repair completes, open Outlook again.

ScanPST works for minor corruption but may fail with heavily damaged PST files.

4. Update Outlook and Windows

Outdated updates can cause conflicts and instability. Keeping everything updated helps you stop Outlook from automatically closing due to compatibility issues.

Steps:

  1. Open Outlook.

  2. Go to File > Office Account > Update Options.

  3. Click Update Now.

  4. Open Windows Settings > Windows Update > Check for Updates.

Restart your computer after updating.

5. Create a New Outlook Profile

A corrupt profile can also lead to crashing or auto-closing issues.

Steps:

  1. Close Outlook.

  2. Go to Control Panel > Mail > Show Profiles.

  3. Click Add.

  4. Create a new profile and reconfigure your email.

  5. Set it as Always use this profile.

Launch Outlook using the new profile and test stability.

6. Repair Office Installation

Broken or missing Office program files can cause Outlook instability. Repairing Office helps restore core components.

Steps:

  1. Open Control Panel > Programs and Features.

  2. Select Microsoft Office.

  3. Click Change.

  4. Choose Quick Repair.

  5. If needed, repeat with Online Repair.

This refreshes Outlook’s internal structure and often stops sudden closing issues.

7. Check Antivirus or Third-Party Conflicts

Some antivirus tools mistakenly block Outlook processes, causing it to close abruptly.

Try:

  • Temporarily disabling antivirus

  • Adding Outlook to the antivirus exclusion list

  • Updating or removing third-party plugins like CRM connectors

If Outlook behaves normally after this, the conflict is confirmed.

8. Reduce PST/OST File Size

Extremely large PST or OST files can overload Outlook and cause sudden shutdowns.

To control file size:

  • Archive older emails

  • Empty Deleted Items and Junk folders

  • Use Compact Now under File > Account Settings > Data Files

A smaller data file improves Outlook stability.

9. Use an Automated Solution for Severe Corruption

If none of the manual methods work, your PST file may be heavily corrupted. In such cases, the quickest and most reliable method is using a dedicated repair solution.

A highly effective option is SysTools Outlook Recovery Software, which repairs corrupted PST files and restores them to a healthy, error-free state. This helps stop Outlook from automatically closing due to deep-level corruption that manual tools cannot fix.

Final Thoughts

If you’re trying to figure out how to stop Outlook from automatically closing, the key is identifying the root cause. It could be faulty add-ins, a corrupt data file, outdated software, or even antivirus interference. Start with simple checks like Safe Mode and add-in removal. If data corruption is involved, repairing your PST file is essential. And if manual fixes don’t help, an automated repair tool can solve severe corruption instantly.

With these methods, you should be able to prevent Outlook closing by itself and regain a smooth, stable experience.