With the large deployment of Windows 10 across the company I work for I have noticed a hand full of complaints about computers going to sleep randomly. Even when the sleep settings are set to never sleep. At first, I just brushed it off as user error. I was thinking maybe the screen was just turning off to save power or the system was hibernating instead. But after working with a few of the users I realized something was up.
I personally setup all the power settings for a few users. Then, later on, I would hear that it went to sleep while they were on the phone for just a few minutes. So I started doing some research and I found this hidden power setting called “System Unattended Sleep Timeout”.
What is System Unattended Sleep Timeout?
The way I understand it is that the System Unattended Sleep Timeout is designed to be the sleep timer Windows uses when a computer that is already asleep wakes up because of a none user event.
For example, if the computer is sleeping and a scheduled task like a virus scan or something wakes it up. Then Windows will use the Unattended Sleep Timeout values to determine when the computer needs to go back to sleep. The values seem to default to 2 minutes.
But for some reason that I am still unsure of this timer kicks in and is used when the computer is already awake.
How to change the System Unattended Sleep Timeout
The setting is hidden by default. But you can unhide it with a registry tweak.
Go to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\238C9FA8-0AAD-41ED-83F4-97BE242C8F20\7bc4a2f9-d8fc-4469-b07b-33eb785aaca0
Then change the Attributes setting to “2”.
Now you should be able to see the hidden setting in the advanced power options!
Change the values to a higher number and that should fix the problem. You may even be able to set them to “0” but I have not tested this yet.
The downside to this fix is that it may mess with some scheduled task. I have not seen any problems yet but that is something to keep in mind.