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Thunderbird 78.10.1 very slow opening messages especially with attachments

  • 3 replies
  • 1 has this problem
  • 9 views
  • Last reply by sfhowes

tom255
tom255
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Recently Thunderbird 78.10.1 is very slow opening messages. It takes from 2 to 5 minutes. It never used to do this. I have Windows 10 Home 64 bit. I recently updated to Thunderbird 78.10.2 and it is still happening. Any ideas?

Recently Thunderbird 78.10.1 is very slow opening messages. It takes from 2 to 5 minutes. It never used to do this. I have Windows 10 Home 64 bit. I recently updated to Thunderbird 78.10.2 and it is still happening. Any ideas?

All Replies (3)

sfhowes
sfhowes
  • Top 10 Contributor
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What is the antivirus and its settings for email? Run Windows in safe mode to test for interfering startup apps.

tom255
tom255 Question owner
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Thanks for replying. I tried turning off Real-Time Scanning in McAfee and it didn't help. Then I tried running Windows in safe mode and that didn't help - I gave up waiting for an email to open after waiting over 2 minutes. This is so frustrating - this all started happening in the last month

sfhowes
sfhowes
  • Top 10 Contributor
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I don't think you want to turn off McAfee Real-Time scanning, but the mail scanning options should be disabled:

https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues#McAfee

But if the problem remains in Windows safe mode, look through the list of items here to see if any of them apply to your setup.