unplug the plug

that’s the only really safe thing to do – when you’re in trouble, or you got a worm/trojan/virus/hacker etc (or, more recent, the conficker-virus, about 5M victims)

as long as you’re unplugged, you can do ALL the troubleshooting, pinging, DNSing etc that you want to do, mostly without messing things up more than they are already

most admins are somehow helpless without any network, but for that case you carry a few different Boot-CD/DVD with you (with various OS, just in case one won’t boot because of some BIOS compability issue etc)

unfortunately the whole activation/serial number issue is keeping admins from doing their work – being online is dangerous with an unpatched system, but to fully run the system you need to activate, but to do that you gotta be online … don’t you just learn to love linux?