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Is there any way to uncomact the inbox and go back to a folder with files in it?

  • 3 replies
  • 2 have this problem
  • 8 views
  • Last reply by peter_wade

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I am running Thunderbird 24.5.0 on Windows 7 Home Premium 64 bit.

I let my inbox get rather big and Thunderbird decided to compact it, it seems to be just one file now. Now my virus checker says it has found a threat in the file InBox and wants to delete the file. I don't want to just delete my entire inbox. I was hoping that if I could uncompact it the virus checker could find and delete just the message causing the problem. I have deleted a lot of junk messages so the inbox is not as big now but I can't find any way of reversing the compression.

I am running Thunderbird 24.5.0 on Windows 7 Home Premium 64 bit. I let my inbox get rather big and Thunderbird decided to compact it, it seems to be just one file now. Now my virus checker says it has found a threat in the file InBox and wants to delete the file. I don't want to just delete my entire inbox. I was hoping that if I could uncompact it the virus checker could find and delete just the message causing the problem. I have deleted a lot of junk messages so the inbox is not as big now but I can't find any way of reversing the compression.

All Replies (3)

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Compacting is not compressing nor zipping.

Compacting removes 'marked as deleted' emails to tidy the file and create space.

When you delete an email, it is .marked as deleted' and from your point of view, it disappears from the Inbox folder and reappears in the 'Deleted' or Trash folder. In reality, it is still in the Inbox, hidden from view and 'marked as deleted'. This means it is easy to recover deleted mail.

When you compact a folder , it removes the 'marked as deleted' email. If you do not compact on a regular basis, there is a chance that the file will become corrupted and then Thunderbird does not know where the end of a 'marked as deleted' really ends, so can delete other good emails.

The Inbox folder has more activity, downloading, moving, deleteing than other files. The Inbox should be used as an Inbox and emails should be moved to appropriate folders for storage. It is advised to keep the Inbox low in email numbers and create regular backups.

Folders in Thunderbird are mbox files, when emails are downloaded they are stored one after the other in a single file. So, it is also a good idea to keep files small. Archiving by month and keeping folder structure is one method you can use to do this.

Info on Maintaining a healthy Thunderbird:

Info on Compacting:

Info on Backup:

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Re: Anti-virus

Because emails are stored one after the other in a single file, anti-virus programs are not always designed to recognise this, they only see one file.

What you could do is create a folder on the desktop and save the emails as individual .eml files in that folder. Right click on highlighted emails and choose 'Save as' options. Select the created desktop folder where to save the email. There is an addon called ImportExport tool which can offer more options; see link below and image..

Then scan the created desktop folder containing the .eml email files. the anti-virus will then pick up the actual email that it believes is corrupt. Once you know this, you can delete the actual email from the Inbox.

Remember that after emptying Deleted and Junk folders to right click on folder and select Compact to remove all traces.

Please read this article on Anti-Virus software.

Modified by Toad-Hall

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Thank you for the information.

I have been exporting e-mails I want to keep to preserve them if the inbox gets lost. I will keep on doing this and virus scan them as well to see if I can find the rogue one and I'll have a look at the article on anti-virus software as well as the other ones.


Thank you for your Help

Peter