Thanks Bert. Yeah, I did run the AC Utilities several times already and it doesn't seem to do the trick. Since i already replaced the switch, if it freezes again, I am gonna get rid of the Vista machine for sure. HAHA!!!

And David, what I did on the MAIN PC is I configured the anti-virus software not to scan my AC folder. Because I am afraid if I disabled the entire anti-virus software altogether, then i wont have any virus protection? So should I do the same thing on the workstations too?

I will keep you all posted on this...
Please pray for me, guys!!!
Many thanks to everyone.
Tommy ;-D