I've had the most frustrating fortnight as my ISP changed mail servers and I couldn't access my primary email even though I'd followed instructions to the letter on changing the POP and SMTP settings.
I thought it was just me being dumb or something. Then when the ISP got battered on Net forums and Twitter over stuck email, I felt a little better.
But when I could finally dial through to the server, only to have it reject my password, I thought it was just me again. Especially as it accepted the same password when I checked the Web version of my mail.
Tech service was of no help -- if only because they couldn't even be reached. I lost patience and hung up after being put on hold for more than a few minutes.
So I toyed with all my settings. And then, amazingly, after a minor change, everything worked and my email was back in business. Where the prompt asked for username, I had duly given just my username. It really wanted email@example.com. The java error window couldn't express that, it could only tell me that it was rejecting my password when the problem all along was the username. Or more properly, firstname.lastname@example.org. It must've been programmed by a geek who didn't know how to say what he meant.
Now I feel kinda smug that I solved all that without tech service. They can go and tie up the phone lines and keep not saying what they mean.