Can't Access Desktop Files from the Laptop

I have an Insprion 8500 with the truemobile card.  I've upgraded both the laptop and desktop to WPA security.  They both have the correct passwords.

I can access the internet wirelessly from the laptop.  The desktop can access files on the laptop that I've marked for sharing.  The laptop can ping the desktop and see the desktop when I do a net view command.  The laptop cannot access any of the shared files on the desktop.  It gets a security violation.  If I go to Microsoft Networks, the laptop gets security violations when it tries to access its own shared folders.  I'm an adminstrator on the laptop. 

Both machines are running Windows XP Pro.

I've uninstalled the firewall software on the desktop.  I had this working after I upgraded the router, both computers and the truemobile card for WPA security, but for some reason, the laptop can't access anything on the network anymore.

How can I get the laptop to access the files and the printer attached to the desktop?  I have file and printer sharing turned on.