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Thunderbird hangs on "connected to imap.ionos.co.uk". SOLVED caused by ESET/NOD32

  • 5 replies
  • 2 have this problem
  • 9 views
  • Last reply by Bill Peters

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Last night, everything was working OK. This morning Thunderbird would not connect to the email server. It now hangs on "connected to imap.ionos.co.uk". ISP says they have not changed anything. I am using their suggested settings STARTTLS and SSL/TLS and suggested ports. As Thunderbird says it is connected, it seems to be a problem the ISP end. They blame Thunderbird. I have tried turning down the security to use outdated security protocols TLS 1.0 and 1.1 using the config editor but, with the ISPs suggested settings, it still does not work. Changing the security in Thunderbird to NONE allows Thunderbird to download and send emails.

Any suggestions please?

Last night, everything was working OK. This morning Thunderbird would not connect to the email server. It now hangs on "connected to imap.ionos.co.uk". ISP says they have not changed anything. I am using their suggested settings STARTTLS and SSL/TLS and suggested ports. As Thunderbird says it is connected, it seems to be a problem the ISP end. They blame Thunderbird. I have tried turning down the security to use outdated security protocols TLS 1.0 and 1.1 using the config editor but, with the ISPs suggested settings, it still does not work. Changing the security in Thunderbird to NONE allows Thunderbird to download and send emails. Any suggestions please?

Modified by Wayne Mery

Chosen solution

firefox1117 said

Hi, are you using Eset firewall? There seems to be an update was released which blocks some parts of Thunderbird. Try to disable it by right clicking on the icon in the system tray > Advanced settings > Web and email, and disable the options there.

Ah, that worked perfectly for me, thanks very much!

Read this answer in context 👍 1

All Replies (5)

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The same thing has been happening for me (and other users in this support forum) today using other email services (e.g. Gmail, in my case), which leads me to believe the problem isn't specific to your ISP.

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Hi, are you using Eset firewall? There seems to be an update was released which blocks some parts of Thunderbird. Try to disable it by right clicking on the icon in the system tray > Advanced settings > Web and email, and disable the options there.

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Chosen Solution

firefox1117 said

Hi, are you using Eset firewall? There seems to be an update was released which blocks some parts of Thunderbird. Try to disable it by right clicking on the icon in the system tray > Advanced settings > Web and email, and disable the options there.

Ah, that worked perfectly for me, thanks very much!

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Thanks firefox1117. Yes, I am using ESET and your suggestion worked for me too.

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I had same problem. Turning off SSL/TLS checking in ESET fixed the problem.

Over aggressive security!!

Thanks, Bill Peters