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Thunderbird Error message: log-in to mail server failed

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  • Last reply by DavidGG

susie
susie
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I've started to get an error message when I open Thunderbird - failure to log-in to mail server. It continues like this for hours, then starts opening normally ....until the next time. I can access my mail through Outlook but I much prefer to use Thunderbird. I use Windows 11 and am very tech-stupid, but perhaps someone can tell me how to solve this in really simple words! Thank you all so much

I've started to get an error message when I open Thunderbird - failure to log-in to mail server. It continues like this for hours, then starts opening normally ....until the next time. I can access my mail through Outlook but I much prefer to use Thunderbird. I use Windows 11 and am very tech-stupid, but perhaps someone can tell me how to solve this in really simple words! Thank you all so much

All Replies (1)

DavidGG
DavidGG
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What do you mean it continues like this for hours? Does it keep showing that error message until it finally succeeds? Can you normally use Thunderbird until then otherwise?

Do you have other accounts listed in Account Settings in Thunderbird that you don't have in Outlook?

If you're using a VPN, disable it and see whether that makes the problem go away. If it does, check whether your VPN has an option called split tunneling which would allow you to let Thunderbird bypass the VPN.

Start Thunderbird in Troubleshoot Mode. The following article explains how to do that and why it can be useful to help identify the cause of a problem:

https://support.mozilla.org/kb/troubleshoot-mode-thunderbird

What's your operating system? If Windows, start in Safe Mode with Networking mode. You may have to connect your computer to the router with an Ethernet cable, WiFi is disabled in Safe Mode:

https://support.microsoft.com/help/12376/windows-10-start-your-pc-in-safe-mode

Does any of that make the problem go away?