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Attempts to compact Thunderbird email folders have filled up my disk storage

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  • Last reply by david

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Help! I believe that repeated unsuccessful attempts to compact my overly large inbox folder have resulted in all of the available space on my hard drive being taken up by incomplete temporary MBOX files. I want to know how I can get these temporary files out of the way. Thunderbird 115.5.0, 64-bit, Windows 11.

Background: My inbox is admittedly way too large, but in the past I have compacted it regularly without problems. Recently, after deleting many messages, moving some other messages to other mail folders, and emptying the trash, I tried to compact all folders (apparently including folders for another email account), as Thunderbird suggested. That apparently failed. Then, after deleting more messages, emptying the trash, and emptying my Recycle Bin, I tried to compact just the inbox. After working for a while, Thunderbird gave me a message that compaction had failed due to lack of space on the hard drive. Indeed, the hard drive had only a couple hundred MB remaining! I cleared out a lot of files and freed up several gigabytes of storage on the hard drive, then tried again to compact the folder, only to get another failure message after Thunderbird had been working for a while. I removed still more content and gained about twice as much storage as I had had before the previous try, then tried to compact again, and got the same result after a much longer period of compacting effort by Thunderbird.

Help! I believe that repeated unsuccessful attempts to compact my overly large inbox folder have resulted in all of the available space on my hard drive being taken up by incomplete temporary MBOX files. I want to know how I can get these temporary files out of the way. Thunderbird 115.5.0, 64-bit, Windows 11. Background: My inbox is admittedly way too large, but in the past I have compacted it regularly without problems. Recently, after deleting many messages, moving some other messages to other mail folders, and emptying the trash, I tried to compact all folders (apparently including folders for another email account), as Thunderbird suggested. That apparently failed. Then, after deleting more messages, emptying the trash, and emptying my Recycle Bin, I tried to compact just the inbox. After working for a while, Thunderbird gave me a message that compaction had failed due to lack of space on the hard drive. Indeed, the hard drive had only a couple hundred MB remaining! I cleared out a lot of files and freed up several gigabytes of storage on the hard drive, then tried again to compact the folder, only to get another failure message after Thunderbird had been working for a while. I removed still more content and gained about twice as much storage as I had had before the previous try, then tried to compact again, and got the same result after a much longer period of compacting effort by Thunderbird.

Chosen solution

Are these NSTMP files? If so, just delete them.

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Chosen Solution

Are these NSTMP files? If so, just delete them.

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Found the NSTMP files! There are about 20 of them, including several 8-GB files. Is it safe to delete all of them?

Modified by smithellen

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Yes, they're just failed compaction attempts.

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