Sending Mail issue

Question

Hi, my Outlook is receiving emails but will not send emails out. My email is backed by Gmail. It was working perfectly this morning and then stopped sending out email.

I get this error message:

SmtpSubmissionPermanentException: Smtp submission failed. Server 'smtp.gmail.com' Port '587'. --> Unexpected SMTP server response. Expected: 235, actual: 334, whole response: 334 eyJzdGF0dXMiOiI0MDAiLCJzY2hlbWVzIjoiQmVhcmVyIiwic2NvcGUiOiJodHRwczovL21haWwuZ29vZ2xlLmNvbS8ifQ==
 
Failure code: 1d2e

Answer 1

Hi @AMAR JADHAV, 

Thank you for contacting Microsoft Q&A. 

If Outlook is receiving emails but suddenly stopped sending them through your Gmail account, and you're seeing an error like: 

SmtpSubmissionPermanentException: Unexpected SMTP server response. Expected: 235, actual: 334  This means Gmail is requesting OAuth 2.0 authentication, but Outlook is responding incorrectly, likely due to outdated or unsupported login methods. 

You can try these options: 

Option 1: Use OAuth

1. Remove your Gmail account from Outlook. 
2. Add it again using the Google option (not manual setup). 
3. Sign in through the Google login window, this uses OAuth 2.0, which Gmail requires. 

Option 2: Use an App Password (if you have 2-Step Verification) 

1. Go to Google App Passwords 
2. Generate a password for Mail on Windows Computer 
3. Use this password in Outlook instead of your regular Gmail password. 

SMTP settings (if configuring manually) 

• Server: smtp.gmail.com 
• Port: 587 
• Encryption: STARTTLS 
• Authentication: Required 
• Username: your full Gmail address 
• Password: App Password (not your regular Gmail password) 

You can find more details here: Fix problems connecting your Google account to the Microsoft Cloud - Microsoft Support 

 

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

If you need any further assistance or have additional questions, please don’t hesitate to reach out. I'm here to help.  

Thank you again for your patience and for choosing Microsoft Q&A forum.  

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