Can't forward email with link included
I received an e-mail from a friend's Yahoo account that contained a link that appeared suspicious. I asked my friend if she'd sent it. She said no. She asked that I forward the message to her to another address of hers. I could not. I received an SMTP error. I tried various other SMTP settings, used different accounts etc.. Could not forward the email to her. I tried forwarding it to myself. Couldn't.
As soon as I edited the message to remove the suspicous link, I could forward the message.
Explanation?