Networking between Windows XP Pro SP3 & Windows 7

Dear Windows victims,

I have run out of steam looking for easy ways to share all my files among my 3 pcs: 1 Windows 7, a laptop and Desktop with Windows XP Pro SP3.

My homegroup is OEMGROUP and neither one allows the other to share the files and directories;  I have individually shared the root of the drives and with Mcafee Security 10 have "trusted" all my pcs.

Well any wisdom will be appreciated since I just about gave up the ghost with this "easy network crap"

Sincerely and appreciative in advance,  ER

Fallow the following steps, and thell me if these works.

http://www.howtogeek.com/howto/windows-7/share-files-and-printers-between-windows-7-and-xp/

Att.
Oscar Pedroza