File Sharing between XP & W7

Hi,

I am trying to use the network through wireless router between my Desktop (XP Pro SP3) & Laptop (Win 7 Pro). Able to view my shared folders & printers in each of the PC's but am not able to access them. Getting the following error messages respectively;

Desktop (XP Pro SP3) - Network Name 1234

Laptop (Win 7 Pro) - Network Name ABCD

Additional Info:
1) Windows Resource Tool Kit is installed on Desktop (XP Pro). And have entered the following commands:
net user guest /active:yes
ntrights +r SeNetworkLogonRight -u Guest
ntrights -r SeDenyNetworkLogonRight -u Guest

2) No 3rd Party Firewall software is being used. Have allowed File and Printer Sharing in Windows Firewall on both PC's.

3) Previous my laptop was networked with my desktop. But this is a new desktop. My laptop was in perfect sync with the network with my previous desktop (XP Pro SP2).

Pls assist in resolving this issue.