Today, however, was the first day I tried to do some work on it... and of course now it is not visible to the network and of course it cannot see the network either. I've spent the whole morning racking my brains trying to get this to work, to no avail. In the process I discovered that I AM able to access at least one of the PCs on the network via IP address but I have not been able to get it to resolve names...
It's time to ask for help... Thanks in advance for any assistance.