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Thunderbird break PDF on forward

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

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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)

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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.

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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.

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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.