Hi Mark,
We can try to start the Windows Update service by running the following command:
net start bits
net start wuauserv
and then verify if the following services are running:
Background Intelligent Transfer Service
Windows Update
Regarding this point, the following article can be referred to as reference.
"Windows Update Cannot Check For Updates" error message when you try to install updates
https://support.microsoft.com/en-us/kb/2730071
Best regards,
Frank Shen
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