Simple file sharing is the only file sharing option that is supported in XP home,  so you just need to enable file sharing correctly. There is no file sharing with user/group permission in XP home.

I also suspect most likely there is firewall blocking on XP, check and disable all the firewalls on XP, it can be Windows firewall, antivirus firewall, ZoneAlarm, etc. If no firewall blocking, you should be able to ping XP from Vista.

Also you can access the XP directly from Vista by opening a file browser, and then type following command:

\\type-your-XP-IP-address

Good luck..

[A]
picoHat 
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