my PC is on a small office network, and runs a server. The internet is working fine on the PC, I can ping other computers, and the IP address is correct (it's static), with router and subnet IPs exactly the same as the other computers in the network. However, I cannot ping my PC from any of the other computers in the network, and cannot connect to the server from other computers. Yesterday I was having problems mapping a drive from another computer on the network on the PC, so I went through the network mapping tool, and used the network connections wizard to reestablish the workgroup. I also restarted the computer a couple of times. The drive mapping problem is now fixed, but the ping problem started while I was attempting to fix it. I didn't change any of the firewall settings from their previous state when the connection was working. Thanks for your help

Have you tried disabling the Firewall temporarily? Life is more painless for those who are brainless.