Cripes I should know this.. 2 pcs and a laptop, a,b and c respectively. a-xp pro b,c xp home All are on same workgroup, all have Windows firewall disabled. All have unique names and ips(192.168.1.2/3/4 repsectively). All can get internet and such. I have also rerun home networking setup(but I did not create floppy). From each machine I can see all 3 in the workgroup a and c can see each other and share files/printers etc. b can see a and c and get to their shared files and such. a and c get Access denied when attempting to conenct to b, you may not have permisisiions blah blah blah. I have no clue....
I think if you create identical user names on each PC you will suceed. All of the PCs on my network (all XP Pro) have the same username in the admin group and I have no problems. But then again, my Ubuntu laptop doesn't have any problems either. It might be XP Home screwing with you.
Username's would be the first thing I check. Do you use the same user account on all 3 machines? If you have them setup with different usernames, then you will need to add the usernames into the "shares" permissions to grant access.
I've had that prob when moving my pcs' around and major hardware changes. I just ran the home network on "My" pc and made the disk. I'm using XP home on all 3 of mine.