MSN Mail problem with XP Limited Users

For almost two years, my kids have had no problems getting their email through MSN Mail using their limited XP account.  MSN updated their software recently (don't you LOVE Microsoft??) and now they can't.  We can get it on MY unlimited XP account, or by going to Hotmail.com, but not on their limited accounts.  All we get is the header, and their mail does not appear.

 

My ISP (Verizon) of course says, "it's not our issue", even though they provide the MSN software.  MSN won't help because Verizon provides the software.  Anybody have any ideas?