Networks [XP]Windows File and Printer sharing/home office networking

My brother's computer has just come back from being fixed except they have have kindly wiped the HDD(had too really) and now I need to get it back on our network. However, I've forgotten how to get my computer and his see eachother (they both connect to the internet fine through the router). I've tried using the "set up home/office network" wizard found in My Network Places and telling into to us MSHOME as the workgroup(what my computer and the original network used) and continuing from there, but they never seem to see each other, and once when they did(or rather my brother's was able to see "*****'s computer) I kept getting some error about not having sufficent privilages and to contact the network admin. Both computers are using Win XP with Windows File and Printer Sharing Installed.

 

do either of them have any kind of firewall installed? including the windows one.

if you are really struggling, just start from scratch. make it as simple as possible.

also check the router settings

 

Thanks, I thought about the network firewall hidden in my AV suite thing, although it should have been set to "wireless network" and not "direct connection" as it was.