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The Linux version of Thunderbird repeatedly pops up the error "Unable to connect to IMAP server".

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  • 1 has this problem
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  • Last reply by Matt

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This is a very strange problem. I've had this account set up in Mozilla for at least a couple of years, but this only recently started happening. Thunderbird can download my mail without issue. It allows me to read messages on the IMAP server. It allows me to mark messages as read or unread. Moreover, it doesn't happen consistently. Sometimes, there's a delay in how long it takes for the messages to get marked as read, and then the error comes up, but then a couple of seconds later it will work. This problem is mostly just annoying, and the error message sometimes gets in the way of other programs.

This problem does not happen on the same e-mail account on my Windows 7 PC at home, which also uses Thunderbird. Nor does it happen on any of the other e-mail accounts I have set up in Thunderbird on my Linux workstation.

The particulars of my Linux workstation:

- Ubuntu 16.04 LTS - Thunderbird 52.9.1 (64-bit)

The only difference between this and my Windows 7 workstation is that Thunderbird is the 32 bit version. Thunderbird has the same version otherwise.

I hope this helps someone. Please reply if you need more details.

This is a very strange problem. I've had this account set up in Mozilla for at least a couple of years, but this only recently started happening. Thunderbird can download my mail without issue. It allows me to read messages on the IMAP server. It allows me to mark messages as read or unread. Moreover, it doesn't happen consistently. Sometimes, there's a delay in how long it takes for the messages to get marked as read, and then the error comes up, but then a couple of seconds later it will work. This problem is mostly just annoying, and the error message sometimes gets in the way of other programs. This problem does not happen on the same e-mail account on my Windows 7 PC at home, which also uses Thunderbird. Nor does it happen on any of the other e-mail accounts I have set up in Thunderbird on my Linux workstation. The particulars of my Linux workstation: - Ubuntu 16.04 LTS - Thunderbird 52.9.1 (64-bit) The only difference between this and my Windows 7 workstation is that Thunderbird is the 32 bit version. Thunderbird has the same version otherwise. I hope this helps someone. Please reply if you need more details.

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one of the "causes" of this can be running out of connections to the server. Why it would occur at work more than home I do not know, but try leaving any other device that gets mail from that account turned off and see if you see the issue.

The only other things I can think of is a bad router/internet connection, but I would expect to see other intermittent page load issues like slowness or loss of sites etc in a browser if that was the case. Lastly an edge device that does deep packet inspections on incoming mail ports in your work environment that leads to timeout because it is so slow.