After compressing some mails lost all threads thunderbird

Frustrating!

When you compress emails in Thunderbird, it's possible that the thread structure is lost, especially if you're using a compressed format like .zip or .7z. Here are a few potential solutions to help you recover your threads:

1. Use Thunderbird's built-in compression: Instead of using an external compression tool, try using Thunderbird's built-in compression feature. Go to Tools > Account Settings > Server Settings > IMAP (or POP if you're using POP3) > Advanced > Compress and select a compression format that preserves folder structure (like .mbox or .eml). This way, Thunderbird will compress the emails while preserving the thread structure.
2. Use a third-party add-on: There are several add-ons available that can help you compress emails while preserving the thread structure. For example, you can try Email Compression or Thunderbird Compressor. These add-ons might provide more options for preserving folder structure and thread information.
3. Re-import the compressed emails: If you've already compressed the emails using an external tool, you can try re-importing them into Thunderbird. Go to File > Open Folder and select the compressed folder. Thunderbird should be able to import the emails and preserve the thread structure.
4. Use a third-party tool: There are several third-party tools available that can help you compress and preserve the thread structure of your emails. For example, you can try MailArchiver or Email Extractor. These tools might provide more advanced features for compressing and preserving email threads.
5. Re-create the threads manually: If all else fails, you can try re-creating the threads manually by sorting the emails by subject and date. This might be time-consuming, but it can help you recover the thread structure.

Remember to always make a backup of your emails before compressing or importing them to ensure that you don't lose any important data.