Alejandro,

Not a problem.... I am just wondering about your configuration. I am assuming XP Pro and server 2003 in the same sub-net. If you are not using a domain, then you should create the same users in the server as well as the client, make sure you maintain your users using the Manage Users in the My Computer
XP tends to 'mislead' regarding the actual user name that is passed accross when validating against the server or other computers in the network, that is why you need to manage the users thru the management console.

Ricardo A. Parodi
eSolar, Inc.