Attachments with Long Names

I have a PDF with attachments that have loooong names.  When I double-click the attachment, nothing happens.  I can even right-click the attachment and select "Open File", but nothing happens.  The breaking point seems to be 179 characters.  179 or less works, 180 or more doesn't.  Most of the time.  Every now and again (maybe 10% of the time) the long name opens.

Is there a restriction on length in attachment names?