Ummm.
1st thing to try is open Windows firewall and untick the no exceptions box.
does that work?
Have you updated your antivirus or firewall programs? Installed new security software? They could cause this. try turning them off temporarily and see if that works (you should be able to disconnect from the net at this point, we are dealing with the internal networks here.) MAKE SURE you turn the windows native firewall off, too (start-control panel-security),at the bottom is a link to windows firewall.)
now try it.
If that works, get back to me and I will show you how to configure your firewalls so that they talk.
IF not:
when you have done that, test it. if it works, great. if not then open your network wizard (start-control panel-network setup wizard) on each computer. you want to select the "This computer connects through another computer or residential gateway" or something, then select computer name, select "turn file and printer sharing on" and that should set you right.
Does that work?
Never begin a job by looking at a computer and saying, or even thinking "this won't take long..."
If all else fails, use a bigger hammer.
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