Mouso core worker process

My success was: noting there was an unsuccessful update, KB4577586 (uninstalling Flash Player, in Other Updates); I installed the 20H2 Feature Update; then, KB4577586 reported as "successful", and the computer went to sleep at the first instance!

I think the key was MoUSOCoreWorker.exe was being held up by the failed KB4577586 update, thus keeping Update triggered (thus preventing sleep). Note: I had no extensions/add-ons/plug-ins of Flash Player, anyway.

What I don't understand is why the update status is so pervasive on preventing sleep-mode; I presume throughout the years other pending updates have not impeded sleep as strictly.

Edit: MoUSOCoreWorker can still be in effect even though Update Statuses are all successful. Sleep prevention has returned, but I manually ran the update(s), and sleep ability returned once again.

Got assistance for mine from Microsoft support, this is what they told me -

Press Windows key + X Click Power Options Click Change Plan Settings” next to the option that you have selected. Click “Change advanced power settings“. On the “Power Options” screen, you want to expand each setting and ensure that they allow the computer to go to sleep mode. In my case, the setting under “Multimedia settings” > “When sharing media” was set to “Prevent idling to sleep“. I had to set this to “Allow the computer to sleep“.

Once i did that i found running cmd powercfg -requests showed the dreaded MoUsoCoreWorker.exe had gone.

Hope it works and helps others

Update- it did work. Laptop went to sleep as it should

Here is the fix (worked for me at least).

tl;dr [Run the Windows Update Troubleshooter]

1. Open 'Troubleshoot Settings' (Win Key, start typing it, press it)
2. Press 'Additional Troubleshooters'.
3. Press 'Windows Update'.
4. Run the update Troubleshooter.

Mine found errors and resolved them.

5. RESTART.
6. Open CMD in Admin and run 'powercfg -requests' to see if the glitch is still there (mine had gone at this point)
7. Run Windows Update and look for updates. Now, when I opened mine, there was an error shown 'Failed to Install', I think this was the issue causing that exe to run constantly, and it was the Adobe Flash removal update!

Let that update now hopefully run correctly, and when it says update installed, go back to CMD, press the up arrow key to show last command and press enter to see if the exe isn't listed... hopefully it isn't and all is back to normal.

If memory serves this isn't the first time I've had to run this same process to fix an update issues causing sleep errors.

This is the true legit fix right here. After doing so you'll have to fix the power settings for your Ethernet, Wifi and other devices that ask the computer to remain on if used.

Just throwing my hat in the ring. I am another who is experiencing this issue with MoUsoCoreWorker keeping my computer awake

Installed the update (KB4023057) when it came out and continued to have this issue.
I have since updated to 20H2 and the issue persists.

I have gone through every "solution" in this thread and nothing has fixed the issue for me.

Edition Windows 10 Pro

Version 20H2

Installed on ‎2/‎3/‎2021

OS build 19042.804

Experience Windows Feature Experience Pack 120.2212.551.0

no you have not. if you try my solution, it will work.

Just throwing my hat in the ring. I am another who is experiencing this issue with MoUsoCoreWorker keeping my computer awake

Installed the update (KB4023057) when it came out and continued to have this issue.
I have since updated to 20H2 and the issue persists.

I have gone through every "solution" in this thread and nothing has fixed the issue for me.

Edition Windows 10 Pro

Version 20H2

Installed on ‎2/‎3/‎2021

OS build 19042.804

Experience Windows Feature Experience Pack 120.2212.551.0