XP File Sharing - New Install Problems

Hi

Just changed motheboards on one of my PC's and managed to keep the exsisting XP on the same computer without doing a fresh install. (All New drivers and devices are installed)

I have a media server and I have set up shares/access to the media server.

This new computer no longer sees the shares and when I type \\computer\c$ or \\computer\films I am no longer able to gain access to the server. My other computers see the server fine.

I can remote desktop to and from the new computer but by only using IP address and not computer names. I can ping the new computer but once again only by using IP addresses and not MS names. I am a bit stuck now so can anyone suggest what to do next? Oh and I have de-installed and re-installed MS file and print sharing too. I am not using the simple file share method either.

Hope all above makes sense!

TIA