Either A has stopped being the dhcp server or Hub is set to allow 1 connection or hub has died.
Some ports do die on hubs - DO NOT go and buy a new hub, We have to make sure first.
May I hav the make and model of the hub.
Is the hub set for straight through or cross over.
I am still thinking that the problem is machine A as it is connected to Machine B via direct cable (cross over I hope)
And B can't connect so that should in theroy rule out Hub.
Have you tried a restore point on A to a time when it was working?.
If you do a restore you do not loose any current data and you can undo the restore
Edited by peterm, 08 January 2009 - 03:08 PM.