I have had Gmail POP3 polling running since January using the App password method. No issues and all has been going great. I upgraded from 3.5.0.beta7-dev to 3.5.0.beta8-dev. I immediately received the following error in my admin panel: Connection to the POP3 server is failing with an authentication error. Please check your POP3 settings. I have done the following: Checked everything with Gmail. No issues visible. Recreated a new app password. The original and the new one does not work. Any suggestions on how to troubleshoot or do more investigations to determine the issue? thanks in advance.

Hi there, does this help? [image] Connection to the POP3 server is failing with an authentication error. Please check your POP3 settings Support I recommend turning on 2FA on the account and setting up an App Password for Discourse. The policy change is about the “allow less secure app access” option being deprecated. More info on this here:

No, that does not help. I have had the “app password with 2FA” implemented since January. It is the app password with 2FA that has stopped working. Any other suggestions?

Anything in /logs, or any errors in the mail account? Also, does anything in here help?

I retested email reply system this morning an now it is working. No changes. Nothing net new or different other than upgrade. We will see if it throws another error code.

Gmail POP3 Polling Failing after Upgrade to 3.5.0.beta8-dev

Product Support

NateDhaliwal (Nate Dhaliwal) July 6, 2025, 3:56am 2

Hi there, does this help?

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Gmail POP3 Polling Failing after Upgrade to 3.5.0.beta8-dev

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