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Problem compacting Inbox

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  • 2 have this problem
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  • Last reply by Cameroon

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When I start Thunderbird, I always get this message: The folder 'Inbox' 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.

 How do I verify that I have enough disc space and privileges?  I moved most of the mail in my inbox to other folders and still get this message.  When it is trying to compact inbox, I can not do anything with my e-mail.
When I start Thunderbird, I always get this message: The folder 'Inbox' 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. How do I verify that I have enough disc space and privileges? I moved most of the mail in my inbox to other folders and still get this message. When it is trying to compact inbox, I can not do anything with my e-mail.

Chosen solution

There could be a couple of reasons, but if the Inbox is corrupted then you may start to lose emails.

Please do the following: Move all wanted good emails out of the 'Inbox' and into other suitable folders for organising and storage.

When you have moved everthing you want to keep.....

Make hidden files and folders visible:

In Thunderbird Help > Troubleshooting Information click on 'show folder' button a new window opens showing the contents of your profile name folder.

Close Thunderbird now this is important.

Pop mail accounts are kept in the 'Mail' folder. Imap mail accounts are kept in the 'ImapMail' folder.

Assuming this a pop mail account click on 'Mail' folder click on pop mail account name folder

Delete these files:

  • 'Inbox' mbox file with no extension - this contains emails, but in your case you have moved everything you want to keep.
  • 'Inbox.msf' file. This is just an indexing record of the 'Inbox' file.

Close window - top right x

Start Thunderbird. A new 'Inbox' and 'Inbox.msf' file will be created.

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All Replies (3)

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Seçilmiş Həll

There could be a couple of reasons, but if the Inbox is corrupted then you may start to lose emails.

Please do the following: Move all wanted good emails out of the 'Inbox' and into other suitable folders for organising and storage.

When you have moved everthing you want to keep.....

Make hidden files and folders visible:

In Thunderbird Help > Troubleshooting Information click on 'show folder' button a new window opens showing the contents of your profile name folder.

Close Thunderbird now this is important.

Pop mail accounts are kept in the 'Mail' folder. Imap mail accounts are kept in the 'ImapMail' folder.

Assuming this a pop mail account click on 'Mail' folder click on pop mail account name folder

Delete these files:

  • 'Inbox' mbox file with no extension - this contains emails, but in your case you have moved everything you want to keep.
  • 'Inbox.msf' file. This is just an indexing record of the 'Inbox' file.

Close window - top right x

Start Thunderbird. A new 'Inbox' and 'Inbox.msf' file will be created.

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I have Windows 10 and can not find my Thunderbird mail folder. Can you provide more specific info on how to find the correct file? The explorer function is really more complicated in Windows 10. Also I have moved most of the mails from my inbox, but the last 60 or so will not drag or move to another folder. Any advice on this problem? Thanks Toad Hall (or others) for any other advice you can provide.

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I was able to fix this problem following your instructions. I was finally able to open all the thunderbird email folders and delete the inbox ones. Thanks a lot. Cameroon.