My favorite call from when I used to do tech support involved a bounced email. The caller kept trying to send an email to her minister, but it kept bouncing back as undeliverable.

She thought it had something to do with the church secretary who apparently hated her and might be interfering. She spent about half-an-hour explaining this to me without giving me a chance to get a word in edgewise.

When I was finally given a chance to ask her a question, I asked what email address she was trying to send to. She told me and I said "try it without the 'www.' at the beginning."