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Thunderbird eats up huge memory and becomes stuck after a latest update and after addition of a new mailbox.

SuMo Bot

Dear Thunderbird gurus,

I am using Thunderbird on a MacBook Pro. Several days ago, I updated it following an update notice of mac. I did not notice any problem immediately after the update. Several days later, after I added a new mailbox, it began to behave weirdly. The major symptom is that, after starting-up, it becomes stuck after several seconds. The system monitor shows that Thunderbird is not responding and is continuously increasing its consumed memory, starting from a bit more than 300MB, endlessly increasing up to several or even tens of GB or more, if I do not force quit it. (See my attached screenshots of the system monitor.)

I have tried to exit Thunderbird and start it again, but it doesn't help. I also tried to restart the mac, the problem is still there. Now I have updated my macOS from previous version to Catalina version. However, the thunderbird problem is still the same.

I also tried to install a new version of Thunderbird. But I find that the two versions actually share the same root directories. I do not know how to safely migrate all my mails and settings from the old version to a new version of Thunderbird in the same mac.

Welcome to help me survive this crisis. Thank you!

Carl

Dear Thunderbird gurus, I am using Thunderbird on a MacBook Pro. Several days ago, I updated it following an update notice of mac. I did not notice any problem immediately after the update. Several days later, after I added a new mailbox, it began to behave weirdly. The major symptom is that, after starting-up, it becomes stuck after several seconds. The system monitor shows that Thunderbird is not responding and is continuously increasing its consumed memory, starting from a bit more than 300MB, endlessly increasing up to several or even tens of GB or more, if I do not force quit it. (See my attached screenshots of the system monitor.) I have tried to exit Thunderbird and start it again, but it doesn't help. I also tried to restart the mac, the problem is still there. Now I have updated my macOS from previous version to Catalina version. However, the thunderbird problem is still the same. I also tried to install a new version of Thunderbird. But I find that the two versions actually share the same root directories. I do not know how to safely migrate all my mails and settings from the old version to a new version of Thunderbird in the same mac. Welcome to help me survive this crisis. Thank you! Carl

All Replies (1)

Vahaolana Nofidina

Eventually, I solved the problem by myself. I pretended that I have a new computer and backup the /Profile/Thunderbird folder to an external disk and thoroughly delete the Thunderbird software and related folders and reinstall it. However, I found that copying the entire /Profile/Thunderbird folder back will throw the newly installed Thunderbird into the same problem. I can only copy the email-account folders and some files for the address book to avoid this problem. Thus, I guess the problem was perhaps caused by the malfunction of the indexing of mails in my mac. My mailboxes has a big size of about 8 GB.

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