Windows 10 - reported uptime in Task Manager and Powershell is Wrong

Question

_{Tuesday, June 13, 2017 1:10 PM}

Has anyone else over the last few months noticed that Windows 10 does not keep the correct uptime when you only shutdown and start up your computer?

I use PDQ inventory to monitor Windows computers, and I have noticed that PDQ is reporting that many computers have been up for several days in a row, which I know to be false. When I check the computer, sure enough, the Task Manager and Powershell uptime command shows that the computer has been running for 3 or 4 or 5 or whatever days in a row, even though these computers are shutdown every single day.

Is there a Windows 10 bug/glitch?

All replies (2)

_{Tuesday, June 13, 2017 1:17 PM ✅Answered}

This is a side effect of fast startup.

If fast startup is enabled, shutdown isn't really shutdown, but something closer to "log the user off and then hibernate". Depending on hardware, the power LED will flash when shutdown in this way in the same way that it would if you explicitly told it to hibernate.

With fast startup enabled, uptime isn't reset unless you restart (which does still properly stop everything and reboot from cold).

Disabling fast startup will fix it, but aside from that anything attempting to measure uptime in the way you want will have to be aware of fast startup and handle it appropriately. (Probably by having its own running pocess that measures uptime, and resetting the timer on suspend/resume events.)

_{Tuesday, June 13, 2017 1:12 PM}

I should also add, if I do an full reboot, then the uptime is reset to 0 and things go back to normal. But, for whatever reason, a normal shutdown and normal turn on, these do NOT reset uptime to 0.