Okay it was in indeed the router! What I wrote was correct, the trojan toke over my router and by doing that nothing was detecting it. I hooked up the PC direct to the internet and the problem was gone. So I then resetted the router, flushed out all the settings, reverted to factory settings, reconnected the router and now no problems!
You can close this thread, but make a sticky out of it. It took me some time to figure this one out. Even you guys didn't have a solution for this problem! Maybe it can help others. It seems to be a new trojan that came out. Don't know what the name is or was, but there are articles on internet about but no info on how to get rid of it! Now you have a way to get rid of it. Spread the word!