Dear Marcos, Every 10-20 minutes ekrn.exe shoots to about 50% CPU usage. When I'm typing this post is it happily doing this. I'm not doing anything else. My computer is sitting virtualy idle now. I do not know whether it relates to browsing the web, but if it does, it is browser independent. It happens both with IE and Firefox. After 5-10 minutes CPU usage returns to normal. I've tried: - Reinstalling NOD32 (latest version) - Disabling Windows update (running Vista Home premium here with all the latest updates installed) - Switching browser Could you please instruct me how to find out what is causing this. I can find my way around a computer so feel free to list a bunch of things I need to try.