Well I shut down my both computers, router, and modem and turn them on in this order:
Computer #1
Computer #2
Modem
Router

If I do this i am able to share files from both computers. If I leave the router and modem on and restart both computers I cant share files. Anyone know why?

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How are the computers connected to the router? (as in wirelessly? lan cables?)

I don't know why it works the way you say it does, but I do know that for me, Windows Firewall screws up any file-sharing (which is dumb 'cause during the network setup wizard, it configures the firewall for file-sharing). So I turn off Windows Firewall. I use Zonealarm instead--sometimes it too blocks file-sharing, but only occasionally. Ususally it works.

Are you using Windows Firewall? If so I'd recommend turning it off and using a 3rd-party firewall. Zonealarm works for me--perhaps others can recommend some.

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