I have had an email from my pension provider. It should have had three pdfs attached. It had only two and one of those was damaged. I went direct to my email provider website and was able to get them from there. But Thunderbird only downloaded two of them, and one of those it corrupted. This is not the first time it has happened.
I had the same problem when downloading emails with attachments from yahoo imap using thunderbird.
For now I have found the workaround of disabling mail.server.default.fetch_by_chunks in Tools => Settings => (scroll to the end of the screen) => click on "Config Editor" (on the bottom right side)
I tried the fix and no luck. Actually, if I open the attachment immediately, it is there but after 2 minutes not good any more! Very frustrating. I may have to ditch Thunderbird and just work with Outlook.
