Here is a problem that keeps happening to me. I put my machine in sleep mode before I stepped away from my desk and when I came back I saw my supposed in sleeping mode machine wide awake without any clue why.
This has bothered me for some time what actually caused this to happen. If you are same like me having the same problem and wondering why, here is a quick way to tell.
Simply run the following command from a Dos Prompt window:
This will show the reason as to why a sleeping machine exited sleep state.
If the reason happens to be your mouse that wakes your machine up, here is how to stop it.