stange lineage problem

1st of all, sorry for my english, im going to try to explain it as well as i can.

I played l2 this summer, on retail obviously, when the servers were interlude. I stopped to play for rl reasons. After, i tried to log in, but when i open l2 interlude it reboots my pc on login screen. With kamael it happens too. I tryed to uninstall but nothing changed. Sometimes, i get a blue screen of windows that says i have a problem with gjjec.sys file but i didnt find nothing at google or on my pc. I have a ATI RADEON x1600 PRO. I can run c4/c5 without problems.Any idea? I tried newest and older versions even alternative drivers of the graphic card but it didnt work

I dont want to format it cuz i have a lot of important files here.

thanks.