Sometimes, when I receive (Thunderbird 18.104.22.168 on OS X 10.5) emails with an EPS attachement sent from Mail OS X 10.4, I cannot open the EPS file. Thunderbird shows me 1 file, that can't be opened with any software but text edit.
But, if I forward the email to myself, the forwarded email then has 2 files of the same name. One of the 2 forwarded files can be opened as expected.
What can be wrong here?