Mnjul, you can try to uncheck everything in your startup folder (start-->run-->msconfig) (except for like your AV and/or firewall, you can choose) and reboot. Then start msn 6.2 and see if it works, then check one additional program to start when windows starts, reboot and check msn 6.2 again and go on till you come up with something (or nothing at the end)
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