Repairing data archive...

Why does my program go through the 'Repairing data archive...' function everytime I launch (even after reinstall)?

I had this a while back, it could be any number of things, basically the 'Repairing data archive', is doing what its saying cos the gw.dat file has been corrupted in some way, it could be any of these - virus/HD failing or errors/graphic card corruption/memory corruption/system corruption.. mine was memory corruption which also included, random game exits in game graphic errors (white boxes/textures), its was just a case of time and testing to find out, then i replaced the ram in my pc and have'nt had 'Repairing data archive' since.