Outlook crashes. It doesn't start. It says "Outlook couldn't start last time, safe mode could help you troubleshoot the problem..." How to fix that?

Suleyman Ari 0 Reputation points

Good day,

One day my Outlook crashed and I couldn't restart it. It gave me an error message stating that Outlook couldn't start properly last time and that Safe Mode might help troubleshoot the problem. However, whether I tried starting in Safe Mode or not, a window would open, and the program would instantly crash.

My company's IT team and I have tried several methods to fix the problem, including:

  • Creating a new profile
  • Repairing Office
  • Uninstalling and reinstalling Office
  • Updating the PC, drivers, and all related software
  • Logging out and back in with different accounts
  • Checking if Office was running the 64-bit version

Despite these efforts, we haven't been able to resolve the issue. I suspect the main source of the error is related to the file "mso20win32client.dll."

Thank you for your assistance. Let me know if you need any more information.

Kind regards

Suleyman Ari

A family of Microsoft email and calendar products.
3,105 questions
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  1. Suleyman Ari 0 Reputation points

    Faulty application name: OUTLOOK.EXE, version: 16.0.17531.20120, timestamp: 0x662e73be

    Faulty module name: mso20win32client.dll, version::, timestamp: 0x662e7217

    Exception code 0x01483052

    Error offset 0x000000000023d75d

    Faulty process ID: 0x5414

    Application start time: 0x01daa11832584c21

    Faulty application path: C:\Program Files\Microsoft Office\root\Office16\OUTLOOK.EXE

    Faulty module path: C:\Program Files\Common Files\Microsoft Shared\Office16\mso20win32client.dll

    Report ID : f9fa8da4-a36a-4c04-b153-bc2214369fee

  2. SokiGuo-MSFT 24,031 Reputation points Microsoft Vendor

    Hi @Suleyman Ari

    Thanks for your reply!

    Based on the error message, this issue may occur when the EmailAddress string data value under the Office identity is empty. More information, see: Outlook closes shortly after it is opened.

    Registry path:  Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\Identity\Identities 

    To work around the issue, try the following suggestions: 

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