I was wondering how this could have happened. After seeing the following screen I got suspicious.
When I started to dig into this problem, @cottow pointed me in the right direction. When I opened the Console.app I saw lot’s of errors:
Then I found out that there were some applications I removed a long time ago still polling in the background. You can fix this by removing the .plist files in:
I think it’s good for everyone to take a look at these folders, because there is a big chance you will have some agents there as well.
My laptop got a whole lot faster since I fixed this!