DPD rang the doorbell today, a while later I had a new main rig up and running. Wohoo! 
To the problem though: The new machine, running Windows 7 Ultimate x64, has full internet access and in general is working flawlessly. As far as the other machines on the network are concerned though, it doesn't exist. And the new machine won't ping them either.
It can ping the router fine, but anything else gives me "Destination host unreachable". None of the machines are in any homegroups and they're all on the same subnet and workgroup.
Any ideas...?

To the problem though: The new machine, running Windows 7 Ultimate x64, has full internet access and in general is working flawlessly. As far as the other machines on the network are concerned though, it doesn't exist. And the new machine won't ping them either.

It can ping the router fine, but anything else gives me "Destination host unreachable". None of the machines are in any homegroups and they're all on the same subnet and workgroup.
Any ideas...?