5 ms·

I like Thunderbird, but several months ago a strange bug happened that caused one sent message to overwrite another sent message (IMAP account). I've noticed on

I like Thunderbird, but several months ago a strange bug happened that caused one sent message to overwrite another sent message (IMAP account). I've noticed only because I needed to resend contents of both messages, and I was really surprised to find that Thunderbird overwrote contents of one message with another (Subject of the overwritten message was intact). It was a one time bug and it might be caused by my IMAP provider, not Thunderbird, but still I'm worried. I keep almost all my emails, dating back to middle of 90s (although in different formats and accounts), and I would like to be 100% sure that all of them are intact. Now I don't have that peace of mind.

shakna 5y ago
IMAP emails are all addressed by a 32bit UID. Overwriting it would require that you experienced a hash collision, data race, or that your IMAP provider sent out the wrong set of IDs. It's incredibly unlikely to be Thunderbird's fault.
- anticodon 5y ago
  I've checked again. Only one letter was corrupt and only Subject line was corrupt. I've chosen to fix folder index from folder properties, and voila! The message was fixed. It wasn't an overwritten message or IMAP bug, it was some corruption of the Thunderbird folder index.
  - shakna 5y ago
    That index is originally created by your IMAP provider - they sent the wrong set of IDs (usually because of a race condition). When you run a fix, Thunderbird checks to see if the provider screwed anything up. It was an IMAP bug.
    - jcranmer 5y ago
      Not true. The "folder index" being referred to in Thunderbird is the local .msf database which is constructed by Thunderbird to provide its own local information about messages in the folder. Repairing it means throwing away all the local data and requerying it from the IMAP server (or in the case of a local folder, reparsing the mbox file). The corruption bug likely lay with Thunderbird and not the IMAP server.

shakna 5y ago

IMAP emails are all addressed by a 32bit UID. Overwriting it would require that you experienced a hash collision, data race, or that your IMAP provider sent out the wrong set of IDs. It's incredibly unlikely to be Thunderbird's fault.

anticodon 5y ago
I've checked again. Only one letter was corrupt and only Subject line was corrupt. I've chosen to fix folder index from folder properties, and voila! The message was fixed. It wasn't an overwritten message or IMAP bug, it was some corruption of the Thunderbird folder index.
- shakna 5y ago
  That index is originally created by your IMAP provider - they sent the wrong set of IDs (usually because of a race condition). When you run a fix, Thunderbird checks to see if the provider screwed anything up. It was an IMAP bug.
  - jcranmer 5y ago
    Not true. The "folder index" being referred to in Thunderbird is the local .msf database which is constructed by Thunderbird to provide its own local information about messages in the folder. Repairing it means throwing away all the local data and requerying it from the IMAP server (or in the case of a local folder, reparsing the mbox file). The corruption bug likely lay with Thunderbird and not the IMAP server.