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How do I fix thunderbird from not responding after I drag an email into another folder? (caused by Windows Defender?)

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  • Last reply by Toad-Hall

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I have the same problem on two different computers. When I drag an email from my inbox into another folder thunderbird hangs and I get a message that it is not responding. After several seconds the email will eventually move into the desired folder, but those seconds it takes really start to add up when I am moving sometimes over 100 emails at a time.

I have the same problem on two different computers. When I drag an email from my inbox into another folder thunderbird hangs and I get a message that it is not responding. After several seconds the email will eventually move into the desired folder, but those seconds it takes really start to add up when I am moving sometimes over 100 emails at a time.

Modified by Wayne Mery

Chosen solution

re :I am only using windows defender. Then windows defender is your AV. You need to make thunderbird folders exempt from scanning. Try this info: https://support.microsoft.com/en-gb/help/4028485/windows-10-add-an-exclusion-to-windows-defender-antivirus

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Start *Windows'* safe mode with networking enabled - win10 https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode

Does problem go away? Please reply to let us know results.

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OK, as per your instructions I started my computer in safe mode with networking enabled and the problem did go away while in safe mode.

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What anti virus are you using? That is the most common cause of freezing. The anti virus locking the files Thunderbird is using to do yet another one of those file scans that found nothing the last 500 times they scanned the same data. Contention is not something some of those anti virus programs consider and Thunderbird does not handle it all that well.

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I am only using windows defender. I have not installed any anti virus software on my computers.

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Chosen Solution

re :I am only using windows defender. Then windows defender is your AV. You need to make thunderbird folders exempt from scanning. Try this info: https://support.microsoft.com/en-gb/help/4028485/windows-10-add-an-exclusion-to-windows-defender-antivirus

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That solved the problem. I excluded the thunderbird profile folders found in AppData Thank You for your help!

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Good to hear all is working better than before.