Why won't my PC with Vista go to sleep when it is not active?

I have an HP m8020n. I can put it into sleep mode manually, and it will stay in sleep mode until I wake it up with the keyboard or the mouse (or until something like my antivirus software is scheduled to run).

However, it won't go into sleep mode automatically. I've created a custom power management profile and tinkered with the advanced settings and told it to sleep after 10 minutes of inactivity, but it just won't do it.

My first thought was that something was continually telling the PC to stay awake so that it could not go to sleep, but then I figured that that same process should also make it wake up right after I made it go to sleep manually.

Any theories or suggestions about where to look?

Why won't my PC with Vista go to sleep when it is not active?spyware remover

Go to Control Panel; System Maintenace; Power Options;

and under Preferred Plans choose Balanced or High Performance

This happened to me before because I choose a Power saver plan and after changing it I never had this problem again.

Why won't my PC with Vista go to sleep when it is not active?virus removal

sleep and hibernation mode are nothing but trouble they screw up more things than you can fix%26gt;turn off or use screen saver
Well it's possible that if you had a downloading client in the background or something along those lines that was still sending information it could prevent the computer from going to sleep.