Seems to be on some Vista computers, that you cannot turn it off !!
Therefore, you could set it to not turn off for 15Hrs (ie overnight and more)

You could use this batch file (ie save to Notepad, the save as, all files, PConfig1.bat, then run it with Administrator rights (just right click on it)
Anyway, here it is, I found the batch file here: http://www.howtogeek.com/howto/windows-vista/disable-power-management-on-windows-vista/

Let me know if it works

 

did you check the settings in the bios as well? donno about acer laptops but I can do this settings in my dell laptops bios...

 

The "workaround" I provided above was because many users are reporting this issue, even if Sleep (or anything to do with Power Management (proprietory or windows) is turned off, in Vista (on some laptops)

Therefore actually turning it on (rather) and setting it for a long delay (many hours) seems to be the best answer

 

Setting a long delay worked. I set it to 100 hours and so far so good.

 

Thanks for the update :grinthumb

 

I didn't say I doubt that but I have 3 laptops (dell, lenovo, hp) running Vista without this kind of problem. so, nice workaround but this to me seems not be a common problem in vista.
I do alot of workarounds every day but I rather find a solution than working everything around. no offense but thats lazy or maybe I am too german at this point...