in reply to Using Net::SMTP to send pdf attachment
I just happen to be working on a program that I thought was using Net::SMTP but, when I switched over to my editor, it looks like I was wrong and it's using MIME::Lite
The MIME::Lite stuff here is a lot clearer than the Net::SMTP stuff from our other scripts if I'm remembering correctly - if you can use it, then I'd recommend that you do.
If you are stuck using Net::SMTP for whatever reason I would first take a look at this node to see if it's of any help (it has info on installing modules in situations where you may not think you have the ability to do so).
If that's not helpful, here are a couple of notes you might find useful, dealing with the problem you're running into: