When you try to download an e-mail message from a POP3 server in Microsoft Office Outlook 2010, it takes much longer than expected. For example, when you download a 1-megabyte (MB) message, the download process may take as long as 15-20 minutes. I was experiencing it on Windows 7 but I now have an XP SP3 user who has the same problem. I have had 50KB file sitting there waiting to download.
I found this KB article that pretty much describes it except for taking an hour, but the fix doesn't work on my operating system, looks like it is more for Vista.