Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Avatar for Username

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

This thread was archived. Please ask a new question if you need help.

Thunderbird break PDF on forward

  • 3 replies
  • 2 have this problem
  • 10 views
  • Last reply by sfhowes

Luciano983
Luciano983
more options

Hi there, if I try to forward a message with PDF attachments the recipient can't open it due to corrupted file.

Thunderbird 60.5.0. I can reproduce this issue on: Windows 7, Windows 10, Osx 10.x.

I've already checked antivirus and os configuration. Nothing seems to fix.

During the forward I've noticed that the attachament size it smaller than the original file size.

Hi there, if I try to forward a message with PDF attachments the recipient can't open it due to corrupted file. Thunderbird 60.5.0. I can reproduce this issue on: Windows 7, Windows 10, Osx 10.x. I've already checked antivirus and os configuration. Nothing seems to fix. During the forward I've noticed that the attachament size it smaller than the original file size.

All Replies (3)

sfhowes
sfhowes
  • Top 25 Contributor
more options

There is a description here of the difference between TB and Outlook with encoding attachments. I wonder if it would make any difference if you changed TB to encode as 'quoted printable' by switching (double-clicking) the preference mail.strictly_mime to true in Config. editor (Tools/Options (Mac: Preferences)/Advanced/General).

If the recipient is using TB, there's another preference that might help with corrupted attachments: set mail.server.default.fetch_by_chunks to false.

Luciano983
Luciano983 Question owner
more options

Hi sfhowes, unfortunately this doesn't fix the issue. I've set mail.strictly_mime to true but yet the attachments is broken.

This happens only with forwarding. If I save the PDF locally and attach it to a new message the file is ok.

Anyway I think this has nothing to do with the recipient.

sfhowes
sfhowes
  • Top 25 Contributor
more options

This might be caused by a bug introduced in TB 60.5 that affects attachments. There is a preview of version 60.5.1 available that you can try and see if it makes any difference.