Unable to share files and printers between Vista and XP

[Guest Mr Mike]

Here's my problem. Added new Vista Ultimate laptop to home network.

Was able to share files on 3 XP PCs and Share Printers on XP PCs.

Norton Internet Security Expired and I renewed.

Vista Laptop no longer able to see other XP File Shares and Printers.

After trying to configure, decided to uninstall NIS.

Still unble to share XP file shares and printers.

Vista Laptop can be seen by XP PCs occasionally.

Vista network center shows network to be private - Check!

File discovery is ON - Check!

File Sharing is Custom. When I try to change to ON, and apply,

nothing changes.

Turned off Simple Networking on 1 of 3 XP PCs. No change.

 

Can anybody help?