Windows 7: Win7 64 to Win7 32

Hi Guys,
I have a Dell T7400 Win 7 64bit machine cabled into an ATT Uverse router (used to be LinkSys wrt54gs) and have the an issue connecting with win 7 32 bit Toshiba. I can access my macbook pro and vmware os x 10.6.6 machines, as well as an xp laptop. printers and a Roku box. These are all wireless (except VM Mac).
When I click on the Toshiba icon, there is an error saying cannot connect due to firewall or network settings. I can see and access the T7400 from the Mac machines and the xp machine, but cannnot access the Toshiba from these. I can access the T7400 from the toshiba, but no write access. The Toshiba does not see the XP or Mac machines.
I did the advanced network tab, and went thru the local security policies on the Toshiba, but no luck.
Anyone point me into the right direction??
Thanks for the help.
Joe


Update
Turns out to be Kaspersky, though I cannot figure what firewall options to tweak.

Fix.
Oddball. Found the additional tab under packet rules in Kas Firewall settings. Unchecked the block connections if they cannot be prompted, and it works, though it is checked on my main box. Go figure. So Kas users with network problems, this might help.

Post fix update.
Macs would appear and disappear in network view. Found that I could not enable network discovery to stay on. Turned out depended upon upnp service. Started, switched to auto and stable now

Well, I'm glad to see you solved it on your own! That's always a good feeling.

This is nearly a tutorial. Good deal, thanks.