Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Thunderbird Compaction is not Compression, invisible 'delete' tags remove large number of email history

  • 4 replies
  • 1 has this problem
  • 1 view
  • Last reply by Wayne Mery

more options

I am not happy!! Apologies for the long winded detail.

I had selected automatic Thunderbird updates. Earlier this year due a Version Update automatic 'Compaction' messages window presented every time I select a different Email Folder asking me 'Yes' or 'No' (lucky for me). I had the strength to reject this function until in a moment of weakness I allowed it to go ahead.

I interpreted 'Compaction' as meaning 'Compression'!!!! This I've found out is NOT THE CASE. Each 'Compaction' message Window should carry a statement that it is 'NOT COMPRESSION, CAUSES SPECIFIC DATA LOSS'. I had migrated large numbers of historical emails from other email accounts into sub folders which now show NO Email Content at all and I understand I cannot recover these lost emails due to the Compaction process.

Investigation shows that this 'Compaction' process utilises hidden / invisible tags assigned to emails by Thunderbird which determines how the 'Compaction' process will deal with each email / folder.

THIS IS A MAJOR FAILURE OF THE 'COMPACTION' PROCESS PROCEDURE because the User does not see this information on his emailsl / folder content to make an informed decision to consent to the process.

I backed up my Thunderbird email account in 2017 where I hope I can reinstate over a thousand lost emails back into 30 + sub folders in the next 2 weeks. However, carrying out a 'Restore' to the original Source of the Backup there is no information how Thunderbird will tag these emails during the restore process AND in the future.

I want to lock out Thunderbird Compaction, it is unsafe, causes significant problems to the User due to lack of visibility of the 'Delete status' tag assigned by Thunderbird to each email / folder(?).

Note : I have tried setting the individual Folder 'Retention Policy' via 'Properties' to no deletion but still get the 'Compaction request' window appearing so what am I to believe?

I am not happy!! Apologies for the long winded detail. I had selected automatic Thunderbird updates. Earlier this year due a Version Update automatic 'Compaction' messages window presented every time I select a different Email Folder asking me 'Yes' or 'No' (lucky for me). I had the strength to reject this function until in a moment of weakness I allowed it to go ahead. I interpreted 'Compaction' as meaning 'Compression'!!!! This I've found out is NOT THE CASE. Each 'Compaction' message Window should carry a statement that it is 'NOT COMPRESSION, CAUSES SPECIFIC DATA LOSS'. I had migrated large numbers of historical emails from other email accounts into sub folders which now show NO Email Content at all and I understand I cannot recover these lost emails due to the Compaction process. Investigation shows that this 'Compaction' process utilises hidden / invisible tags assigned to emails by Thunderbird which determines how the 'Compaction' process will deal with each email / folder. THIS IS A MAJOR FAILURE OF THE 'COMPACTION' PROCESS PROCEDURE because the User does not see this information on his emailsl / folder content to make an informed decision to consent to the process. I backed up my Thunderbird email account in 2017 where I hope I can reinstate over a thousand lost emails back into 30 + sub folders in the next 2 weeks. However, carrying out a 'Restore' to the original Source of the Backup there is no information how Thunderbird will tag these emails during the restore process AND in the future. I want to lock out Thunderbird Compaction, it is unsafe, causes significant problems to the User due to lack of visibility of the 'Delete status' tag assigned by Thunderbird to each email / folder(?). Note : I have tried setting the individual Folder 'Retention Policy' via 'Properties' to no deletion but still get the 'Compaction request' window appearing so what am I to believe?

Modified by Wayne Mery

All Replies (4)

more options

Compacting permanently removes messages that were already deleted. If you want to retain messages for future use, don't delete them, or at least, don't delete them right away. Move them to other folders or archive them outside of TB, e.g. MailStore.

http://kb.mozillazine.org/Compacting_folders

more options

Thank you for the reply but unfortunately missed the issue. These emails were NEVER DELETED by me and why should I store them elsewhere, what is wrong with using TB Sub Folders to reduce Folder size? They were tagged by Thunderbird without authorisation from me with this invisible 'delete' status. These emails were copied over from another email account facility and picked up this 'delete' tag from Thunderbird. I did not lose them until this 'Compaction' procedure was introduced this year and pushed hard on the User to impliment without proper explanation of the dangers of data loss. Currently have all the Folders Retention Policy set to 'never delete' but still get this Compaction message appearing. I backed up my Thunderbird email account in 2017 where I hope I can reinstate over a thousand lost emails back into 30 + sub folders in the next 2 weeks. However, carrying out a 'Restore' to the original Source of the Backup there is no information how Thunderbird will tag these emails during the restore process AND in the future. Any information on this point?

How do I lock out Thunderbird Compaction, it is unsafe, causes significant problems to Users due to lack of visibility of the 'Delete status' tag assigned by Thunderbird to each email / folder(?).

more options

TB doesn't delete or mark as deleted messages without user intervention. Without knowing how you 'copied' the mail from another 'facility', I can't suggest why mail was lost.

But if you want to turn off automatic compaction, the setting is in Tools/Options/Advanced/Network & Disk Space.

more options

I hope you read up on "Compact" because you clearly don't understand the need for it, which is real.