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Thunderbird 140.0.1 is resource hungry

  • 3 replies
  • 0 have this problem
  • 67 views
  • Last reply by Wayne Mery

williamatwood41
williamatwood41

I am experiencing a severe problem with Thunderbird. There are several symptoms: 1) The CPU utilization of Thunderbird is typically 13-19%. 2) Thunderbird declares that it was able to send a message and to save it, but that it experienced difficulty when running filters. 3) Thunderbird is unable to compact a folder. The message received is: 

   The folder 'Inbox on william.atwood@concordia.ca' could not be compacted because writing to folder failed.  Verify that you have enough disk space, and that you have write privileges to the file system, then try again.

4) Thunderbird occasionally gives the following error message: Your message was sent but a copy was not placed in your sent folder (Sent) due to network or file access errors. You can retry or save the message locally to Local Folders/Sent-william.atwood@concordia.ca.

These are the symptoms that I see today. Over the longer term, I saw the following:

1) Thunderbird started to behave strangely several weeks ago. It somehow lost track of what messages it had downloaded, so it started downloading all of the message headers in my inboxes (and other folders). (I have six email accounts that I monitor.)

2) Since all of my accounts are IMAP accounts, with the messages stored on the server, I tried replacing the Thunderbird profile with a copy that I had previously backed up. This seemed to solve the problem for a short time. However, the symptoms soon re-appeared, including high CPU utilization, inability to compact folders, and difficulty running filters.

3) At the suggestion of my employer's help desk, I removed and re-installed Thunderbird. This found the existing Thunderbird profile, and everything seemed to work just fine for a few days. Then, suddenly, everything went haywire, and Thunderbird started re-loading all of the message headers for *all* of my folders (and for all of the accounts), and complaining about inability to run filters or compact folders.

Finally, Thunderbird crashed today. I added notes to the crash report, giving some of the details above. After it restarted, it crashed again. I finally ended up restarting my computer.

Thunderbird version 140.0.1 Windows 11 Edition Windows 11 Enterprise Version 24H2 Installed on ‎2025-‎04-‎30 OS build 26100.4349 Experience Windows Feature Experience Pack 1000.26100.107.0

What can I do to mitigate this problem? It is very difficult to use Thunderbird when it acts like this.

Bill Atwood

I am experiencing a severe problem with Thunderbird. There are several symptoms: 1) The CPU utilization of Thunderbird is typically 13-19%. 2) Thunderbird declares that it was able to send a message and to save it, but that it experienced difficulty when running filters. 3) Thunderbird is unable to compact a folder. The message received is: The folder 'Inbox on william.atwood@concordia.ca' could not be compacted because writing to folder failed. Verify that you have enough disk space, and that you have write privileges to the file system, then try again. 4) Thunderbird occasionally gives the following error message: Your message was sent but a copy was not placed in your sent folder (Sent) due to network or file access errors. You can retry or save the message locally to Local Folders/Sent-william.atwood@concordia.ca. These are the symptoms that I see today. Over the longer term, I saw the following: 1) Thunderbird started to behave strangely several weeks ago. It somehow lost track of what messages it had downloaded, so it started downloading all of the message headers in my inboxes (and other folders). (I have six email accounts that I monitor.) 2) Since all of my accounts are IMAP accounts, with the messages stored on the server, I tried replacing the Thunderbird profile with a copy that I had previously backed up. This seemed to solve the problem for a short time. However, the symptoms soon re-appeared, including high CPU utilization, inability to compact folders, and difficulty running filters. 3) At the suggestion of my employer's help desk, I removed and re-installed Thunderbird. This found the existing Thunderbird profile, and everything seemed to work just fine for a few days. Then, suddenly, everything went haywire, and Thunderbird started re-loading all of the message headers for *all* of my folders (and for all of the accounts), and complaining about inability to run filters or compact folders. Finally, Thunderbird crashed today. I added notes to the crash report, giving some of the details above. After it restarted, it crashed again. I finally ended up restarting my computer. Thunderbird version 140.0.1 Windows 11 Edition Windows 11 Enterprise Version 24H2 Installed on ‎2025-‎04-‎30 OS build 26100.4349 Experience Windows Feature Experience Pack 1000.26100.107.0 What can I do to mitigate this problem? It is very difficult to use Thunderbird when it acts like this. Bill Atwood

All Replies (3)

Wayne Mery
Wayne Mery
  • Moderator
  • Top 10 Contributor

For the performance issue, does it help to remove the status bar from View > Toolbars?

williamatwood41
williamatwood41 Question owner

No. In fact, the CPU utilization today is UP: it now varies between 10% and 21%.

Wayne Mery
Wayne Mery
  • Moderator
  • Top 10 Contributor

williamatwood41 said
No. In fact, the CPU utilization today is UP: it now varies between 10% and 21%.

williamatwood41, please post an update of your status and your version number. Thanks.

Modified by Wayne Mery