have your compared the pop3 stmp settings (check every little detail like authentication enabled, username and passwordannd SSL enabled or not) between it and the working computer?
have you in any way modified your CSV file?
you might have a bad email in your inbox at the server. I had the problem once. it would always say receive 5 out of 15 and then it would stop with an error. when I delete the 5th email at the server, it went away. I use incredimail though