Thanks to everyone who replied, there is so much conflicting information out
there regarding this issue but the one that fixed it for me was to disable
the "IP Helper", "Windows Search" and "Computer Browser" services. If I get
time I might enable them again one by one to see if it's just a single
service that's causing this issue. The post I read originally said to
disable "IP Helper" and "Computer Browser".

I'll check the link regarding McAfee as I do have VS8.5i installed and the
protection pilot agent V3.6.6