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Freezes with Windows 11 - freezes on startup, is very slow to open messages, and occasionally freezes especially when opening a message with attached images

  • 12 replies
  • 1 has this problem
  • 135 views
  • Last reply by Wayne Mery

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Been using Thunderbird for years. Love it. Recently updated my desktop to Windows 11. Ever since then it has froze on startup and is very slow to open messages and occasionally freezes especially when opening a message with attached images.

I'm running a 7th gen i5 which Microsoft says isn't supported but every other program I use on the system works normally. Its just Thunderbird that has "fallen over".

I'd hate to have to give up using it but it is becoming very frustrating to use. For example. On booting the computer this morning, Thunderbird sat locked for just under 3 minutes.

Anyone else experienced this?

Been using Thunderbird for years. Love it. Recently updated my desktop to Windows 11. Ever since then it has froze on startup and is very slow to open messages and occasionally freezes especially when opening a message with attached images. I'm running a 7th gen i5 which Microsoft says isn't supported but every other program I use on the system works normally. Its just Thunderbird that has "fallen over". I'd hate to have to give up using it but it is becoming very frustrating to use. For example. On booting the computer this morning, Thunderbird sat locked for just under 3 minutes. Anyone else experienced this?

Modified by Wayne Mery

All Replies (12)

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I did delete and reinstall a couple of days ago. Running 91.2.1 version

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Tried Windows 11 started in safe mode?

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Thanks. I'll give that a try

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Great. Please post your results.

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OK, did the start in safe mode with windows 11. Thunderbird fired up faster than I've ever seen it. It worked perfectly, fast response opening and displaying emails and images.

Did normal restart and back to slow startup. Freeze for a couple of minutes.

I guess there is something in Windows 11 that causes the hiccup.

I also had a look at replacing Thunderbird and tried a couple of other email clients. Nope, nopety nope. I think I'll just live with the new slowness.

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No Antivirus other than the standard Windows defender which I have always run

Modified by pete71

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Please set an exclusion for the Thunderbird profile directory in Defender. https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues

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Wayne Mery said

Please set an exclusion for the Thunderbird profile directory in Defender. https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues

Pete, did that solve your problem?

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Thanks Wayne. Won't be able to check until Monday. I'll let you know.

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Wayne, did what you suggested. No difference. Still freezes at start up and periodically when opening some emails.

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Working in Windows safe mode is definitely significant.

Step 3 of https://wiki.mozilla.org/Thunderbird:Testing:Memory_Usage_Problems lists these possibilities:

  • check that you have the newest version of AV/firewall software, and check with vendor's support site
  • test with antivirus disabled or removed (because disabling isn't always reliable). See AV performance issues for settings and information which may help.
  • on Windows, especially Windows 10, try disabling MS-Windows Search (see next numbered item below)
  • test with firewall disabled or removed Ad-Aware example
  • any software loaded at boot time is a possible cause
  • run only one antivirus, one firewall, one malware (never multiples of each - more is not better)
  • on Mac, try with Time Machine disabled
  • uninstall Thunderbird, then DELETE the Thunderbird PROGRAM directory (not the data directory), then download, reinstall, and retest Thunderbird. If using beta get it from channels.