|If he gives you his username and password, you should be able to create a separate Outlook profile and log in as him, then clear out emails. Be carefull, if the problem is his mailbox is full, it sounds like your using either IMAP or the option to leave messages on server until deleted. By default, Outlook downloads all messages and removes them from the server, so if you setup a profile on your computer all recent messages will end up getting downloaded to your computer and removed before he gets a chance to get them.|
The phone can be your best friend, and most email hosting services I know of allow access to mailboxes from a web browser. A phone call to Verio tech support can solve a lot of problems quickly. If Verio does not offer web access to your email, dump that cheasy service and find a reputable one that does (GoDaddy.com, NetworkSolutions.com, Register.com).
Assume that I already did an Internet search.