Problems re-opening protools session - help please

Hi, I have been having major problems when trying to re-open protools sessions. My computer continually "freezes" when retrieving files and the only way to get out of the system is to turn off and re-start the computer. The program will let me open and work in new sessions but at some point it will freeze the program and from then on I can't open that session. I am running protools v 6.4 with service pack 1 on an ASUS pentium 4 3.2ghz laptop with 1 mb of ram. I have an external firewire HD and all the gear is brand new. I would really appreciate any thoughts and suggestions that you might have. cheers

have you done the cs6 and cs9 update for 6.4? if not, this may help. merry xmas.

Anyone??????