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Authentication Failure

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After opening TB this morning, and initial download of new emails, I suddenly started receiving Authentication Failure while connecting to server imap.gmail.com popup when trying to download new emails on Thunderbird (Supernova). When I close TB and re-open it I see this:

Warning: Potential Security Risk Ahead

Thunderbird detected a potential security threat and did not continue to live.thunderbird.net. If you visit this site, attackers could try to steal information like your passwords, emails, or credit card details.

Can someone help me solve this issue - in as low tech a way as possible?

Thanks, Linda

After opening TB this morning, and initial download of new emails, I suddenly started receiving Authentication Failure while connecting to server imap.gmail.com popup when trying to download new emails on Thunderbird (Supernova). When I close TB and re-open it I see this: Warning: Potential Security Risk Ahead Thunderbird detected a potential security threat and did not continue to live.thunderbird.net. If you visit this site, attackers could try to steal information like your passwords, emails, or credit card details. Can someone help me solve this issue - in as low tech a way as possible? Thanks, Linda

All Replies (2)

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Additional info: If I reboot my PC, I start receiving emails again, but this doesn't last for very long before the authentication failures start again, and I can no longer send or receive email.

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I had this problem for a long time. Today I changed the setting for the maximum number of server connections to cache from 5 to 3 and the problem stopped. This setting in under server settings>advanced. I think problem happens if too many email clients try to access the server. I have 2 phones, 2 Chromebooks, a Windows PC, and a Linux desktop. I changed this setting on all but the phones because I haven't found the setting there yet. I use K-9 Mail on my phones and one Chromebook.