That's usually a sign that there is some form of activity going on, causing the timer to reset before Sleep mode is to be engaged. Wireless keyboard/mice have been known to cause that, though it could also be a program periodically running in the background or even the internet connection. The former can usually be solved by updated software/driver while the latter can be harder to track down. However, one nice test is to see if the same problem occurs with your screensaver. If so you know it's some sort of activity keeping it 'awake' while if the screensaver does work as expected it's likely a problem specific to Seep mode. That should help narrow down the possibilities.
Let us know.
John
I have Vista Home Premium. The good news is that (after some tweaking to Device Mgr) I am able to put my computer to sleep manually and it will stay that way until I wake it up manually. The bad news is that none of existing power plans, or even new ones I create, will work to turn off my display or put my computer to sleep -with one weird exception: If I change one of the power plans to put computer to sleep in one min, this will work. Nothing greater than one min will work. I have reinstalled Power Management and that did not solve problem. Any ideas?

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