I have several computers and only one is having this problem. When attaching a file to an outgoing email, the first file will attach with no problem. When I click attach again for a second file, Thunderbird crashes every time. Size doesn't seem to matter, at least as far as this problem goes. That is, I can attach one file that is larger that the combined two would be and it works just fine, it just will not attach two files. It has only been this way for the past few months. Thunderbird is up to date. Thank you.