Network homegroup permission issue

I'am trying to network Windows 7 and Vista. Watched the video on the internet instructing how to setup a network between different operating systems. Followed every step exactly and when I try to access a PC on the network I get an error message telling me I do not have permission. Tried everything I could think of but no success. Any suggestions as to what I may have set incorrectly or not at all.
Thanks,

 

A common problem with this may be windows 7 network 128-bit encryption, as Vista doesn't have this. Try setting the encryption to 40-56 bit. The webpage below has a screenshot so you can see where to change this.
http://www.dummies.com/how-to/conte...-windows-7-h.pageCd-storyboard,pageNum-4.html