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Thunderbird could not compact folder due to another ongoing process

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  • Last reply by cloud90

cloud90
cloud90
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Several times per day I get the error message: "Thunderbird could not compact folder X due to another ongoing process". X being Inbox, Sent or Trash for anyone of my mail accounts.

I've done some google search, set option "Compact all folders when it will save over 1 MB in total", under Settings -> General -> Disk Space. I would have preferred to set the value lower but 1 MB is the lowest.

For every mail account I've set the options to "Clean inbox when closing" and "Empty trash when closing" under Account Settings->Server Settings->Storing messages.

Mails I want to save I move to other folders, local and others created for that account. My inboxes, sent, trashes etc. all combined contain less than 50 mails/5 MB.

Any thoughts or ideas on how to solve this are welcome!

Several times per day I get the error message: "Thunderbird could not compact folder X due to another ongoing process". X being Inbox, Sent or Trash for anyone of my mail accounts. I've done some google search, set option "Compact all folders when it will save over 1 MB in total", under Settings -> General -> Disk Space. I would have preferred to set the value lower but 1 MB is the lowest. For every mail account I've set the options to "Clean inbox when closing" and "Empty trash when closing" under Account Settings->Server Settings->Storing messages. Mails I want to save I move to other folders, local and others created for that account. My inboxes, sent, trashes etc. all combined contain less than 50 mails/5 MB. Any thoughts or ideas on how to solve this are welcome!

All Replies (9)

Wayne Mery
Wayne Mery
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Reducing Disk Space won't help, but you get an A for effort.

Have you tried starting Windows 10 in safe mode?

cloud90
cloud90 Question owner
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I haven't tried safe mode before your suggestion, did it today and it seemed to make things better. No error messages while using mail accounts.

Now when running Win10 normal again, the messages are back.

Wayne Mery
Wayne Mery
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Thanks for testing.

What AV, and other software do you run? (including backup software)

cloud90
cloud90 Question owner
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Thank you for helping out.

Windows Defender, Malwarebytes and Acronis True Image.

Wayne Mery
Wayne Mery
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Any of those could be your issue. Mostly likely Acronis True Image, if you have it set for continuous backup.

cloud90
cloud90 Question owner
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No continuous or scheduled backup (which kind of defeats the purpose but I do take backups...), but there are several background processes running from Acronis e.g. their active protection.

https://www.acronis.com/en-in/technology/active-protection/

Wayne Mery
Wayne Mery
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That could be causing the issue. See if there is a way to exclude the Thunderbird profile directory.

cloud90
cloud90 Question owner
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I'll create a ticket to Acronis helpdesk and see if my issue (or similar) is something they know how to solve. I'll get back with updates.

cloud90
cloud90 Question owner
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Acronis couldn't help me since I'm running an outdated/unsupported version (True Image 2019). They suggested to uninstall my version, see if Thunderbird works better and if so, install trial version of True Image 2021.

So when I feel Im up to it, I'll start with that, then move over to Malwarebytes and Defender. Rinse and repeat. Something for a rainy day.