Being Prompted for a Password Repeatedly

I am using Exchange 2003 SBS SP2 with Outlook 2003 SP3 (11.8169.8172).

I am connecting to the Exchange server using RPC over HTTPS via a third
party certificate. I have one laptop that for days has not connected and
today finally connected after repeated password prompts. I never get an
option to save the password.

I started Outlook with the "/rpcdiag" option. I noticed one things taht was
different. In the "Exchange Server Connection Status" I see fs1.mydomain.com.
There are a few connections to the directory and to mail all with a status of
"Established". I see two entries for "FS1" where it says it is trying to
connect every once in a while and eventually ends up with a status of
"Disconnected". All of the other laptops work fine except for this one.