#1 Combofix is a tool which should NEVER be run without being instructed to do so by a helper at a forum like this one. It is a very powerful tool and could damage key system files if not run correctly. It produces a log which must be interpreted by somebody familiar with what will be contained in these logs. So we would need to see that log.
#2. Follow the instructions HERE
But begin with one computer only. Disconnect the others and work on only one. If we can get that one clean then we hopefully can clean the others.
Post back with all requested logs, including that combofix log.