I used to be able to access mIRC with NO probs at all but recently all I get is "Unable to resolve server" error. when using "/dns irc.law.emory.com" I also get a unable to resolve, I also cannot resolve through DOS box. I know that my DNS is working for all other things (websites etc). What else could be the problem?

*** nexus.linuxshell.net can't find irc.law.emory.com: Non-existent host/domain

thats because the dns doesn't exist, the person hosting the domain need to resolve this, ntohign you can do.

That server closed/died awhile ago. Find another server to connect to that same network (EFnet) with.