Help with home network needed

["SS" <SS@xxxxxxxxxxx>]

Ive just set up my home PC using XP and my laptop using Vista on a wired 
network and set it up as per these instructions:

http://www.informit.com/articles/article.aspx?p=1165037

Ive set up the sharing on the folders i want to share on both the laptop and 
the PC and all are visible on the PC and laptop however when i click on a 
folder is says:

\\\john\my Documents is not accesible. You might not have permission to use 
this netowrk resources. Access is denied.

I am the only user on the PC and laptop.

any help appreciated