Outlook classic startup issues

Hi Nate, 

Sorry you’re going through this, and I appreciate you sharing the screenshot. 

Just a quick note before we continue: this is a user-to-user community forum, so I don’t have access to your Microsoft 365 tenant, your account, or your device to make changes directly. However, I’m here to support you the best I can within these constraints, by providing clear next steps, sharing applicable resources, and directing you to the appropriate support channels.  

From what I can see, Classic Outlook is showing a prompt asking whether you want to start Outlook in Safe Mode because Outlook may not have started correctly the last time. However, since clicking either Yes or No does not seem to do anything, Outlook may be stuck during launch, or there may be an issue with the Outlook process, add-ins, profile, or cached data. 

Here are some steps you can try: 

1/ First, please close Outlook completely 

• Open Task Manager. 
• Look for any running OUTLOOK.EXE processes. 
• Select each one and click End Task. 
• Then try opening Outlook again. 

2/ Try launching Outlook in Safe Mode manually 

• Press Windows + R. 
• Type: outlook.exe /safe 
• Press Enter. 

If Outlook opens in Safe Mode, the issue may be caused by an Outlook add-in. 

3/ Disable Outlook add-ins if Safe Mode works 

• In Outlook, go to File > Options > Add-ins. 
• At the bottom, next to Manage: COM Add-ins, click Go. 
• Uncheck the add-ins. 
• Restart Outlook normally. 

If Outlook is still not responding after selecting Yes or No, please restart the computer and try opening Outlook again. 

4/ Repair Microsoft 365 Apps 

• Open Control Panel. 
• Go to Programs > Programs and Features. 
• Select Microsoft 365 Apps or Microsoft Office. 
• Click Change. 
• Run Quick Repair first. 
• If the issue still occurs, run Online Repair. 

5/ Create a new Outlook profile 

• Close Outlook. 
• Open Control Panel. 
• Go to Mail > Show Profiles. 
• Click Add and create a new Outlook profile. 
• Add your email account again. 
• Set the new profile as the default, then reopen Outlook. 

Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.  

I hope this information is helpful. Should you have any further questions or need additional assistance, please feel free to share them in the comment below. I'm very happy to help.  

I'm looking forward to hearing your thoughts. 

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