I think I have found a glitch in the Wake up timer function in Windows 7. To start out, I have a Dell Inpiron 1545 (bought over the summer) with Windows 7 Professional (full version RTM) on it. I recently removed my Vista install to make it have only Windows 7 on it. I'll try to give full details of the glitch as best I can. Here goes: In Power Options, I have the Wake-up Timer set to enabled only for Plugged in. It is disabled for on Battery. However, I have noticed a way that you can circumvent this without even thinking about it (or realizing it) and requiring no effort. I have my laptop plugged in every night, and when I go to bed, I put it to sleep. At 1:00 AM, it is set to wake up (just a dummy task in the Task Scheduler that wakes the computer, opens the command prompt, and then closes it, but only if on AC power) so that it can do a virus scan. It should then go back to sleep in a few hours according to the settings I have for sleep on AC power. BUT, the other day I noticed something strange. When I got up in the morning, my anti-virus popped up telling me that the scheduled time was passed, and it would run at the next scheduled time. I thought this was odd because it was plugged in all night (meaning it should wake up like normal, scan, then go back to sleep). I then remembered that I was in the other room using my laptop without the AC cord just before I went to bed. When I was done, I put the laptop to sleep, then plugged it in (remember that order, it's critical). When 1:00 AM rolled around, the laptop thought it was still on battery power (even though it wasn't), and did not wake up. Hmmm.... I kind of shrugged it off, and didn't think much else about it. But today I was thinking...what if you did it the other way? What if you had it plugged in, put it to sleep, then pulled the cord out? So, I created a new task in the Task Scheduler to run in a few minutes, and I set it to run only if on AC power and to wake up the computer to run it. I put it to sleep (plugged in, that's the important part), and then pulled the cord out. In a few minutes, I heard the fan spin up, and the screen lit up fully, then went dim (when the computer realized it was on batter power). I have it set for maximum brightness on AC power, and minimum brightness on battery power. So when it woke up (even though it wasn't supposed to), at first it thought it was on AC power (hence the bright screen). Then when it realized it was on battery power, the screen dimmed automatically. So, to review: if you have a laptop on battery power, put it to sleep, then plug it in, it still thinks it is on battery power. This isn't too big of a deal, but if you have scheduled tasks that should wake the computer to run, they won't (because it thinks that it is still on battery). The opposite also works: if you have a laptop on AC power, put it to sleep, then unplug it (and possibly transport it somewhere), and you have scheduled tasks that should wake the computer on if on AC power, the laptop will still wake because it thought it was on AC power (until it woke up). This could be slightly problematic if you have it in a bag, briefcase, etc... and it comes on when it shouldn't. Mine is set to go to sleep in 15 minutes, but it's possible it could melt some stuff before it went to sleep (I'm not going to test it to find out!!). The task won't run (once it realizes that it is on battery power), but the computer is still awake. That's what I've found. Any comments? Do you think it's isolated to certain combinations of manufacturers (and hence, individual models of computers) and operating systems? Or could it be for all Windows operating systems? Could everybody that reads this please test it and report back with the results? I'm curious to see how widespread it is. If it is a major issue, Microsoft might have to change something in the OS that will actively let the computer know whether it is on battery or AC when it is asleep. If it's on a case-by-case basis, is there a way to fix it? Thanks, keyboardNinja

On my Windows 7 notebook, it will not wake from hibernation to run a task when the system is in a dock. I has AC power all the time. I agree that the behavior you describe is incorrect. Notebook computers have a Systems Management subsystem (SMbus) that monitors things like the wake time, battery, and AC supply. It runs in a low-power state even when the main CPU is off. It should match the power state to the wake rules at the scheduled time and "do the right" thing based on the power state at that moment. There are all sorts of scenarios where this is a problem - waking up in your computer bag while on a plane to do a backup because you put the system to sleep while powered is a very good example. I hope Microsoft can fix this soon with Windows Update.