Thanks for the suggestion, @JA AS , I'm sorry it did not work for me.

I tried running DCU from an elevated (admin) Windows Command Line, and got this (hanging like the GUI app):

C:\Program Files (x86)\Dell\CommandUpdate>dcu-cli /scan
An operation, owned by the 'Service' application, is currently in progress.
DellClientManagementService is busy. Waiting for service to be available...|

If I try deactivating this service I get this error:

C:\Program Files (x86)\Dell\CommandUpdate>dcu-cli /scan
The DellClientManagementService is disabled. To proceed, enable the DellClientManagementService.
Program exited with return code: 3002

If i re-enable the service the error reverts to the original.

It seems like DCU is starting (and keeps busy) the DellClientManagementService without being able to release it to itself.  What are you doing to improve this, @DELL-Cares?

@EngelV Thanks for your suggestion.  I tried it, but it did not help.

Perhaps what worked for me was actually stopping the services and not the folder rename? I reinstalled the application with all Dell services stopped.

i Stopped the service which gave you error and restarted the Aliewanre Update ( Dell Command Update ) it worked fine thank you @blazius1 

I am also having this issue with 3.1.3. on my 7591 2n1 please advise asap.

Thanks for the suggestion @JA AS , I'm tried it now, but it did not help me.

Not sure if anyone is still having this issue, but it presented on several XPS 15 systems in our area. After some trial and error we discovered that these systems had the Dell Support Assist application on them (UWP Version). We uninstalled Command Update and then uninstalled Support Assist, rebooted and then reinstalled Command Update. After that Command Update started working again.

From what we could tell, Support Assist and Command Update don't like to be installed on the same system. And to be honest they're redundant, so best to choose one over the other.

Thanks for your suggestion, @pbbarntt , unfortunately it did not work for me.