Reboot fixed it. Your installer dhould require a reboot.
I ran into that the other day when running As Administrator.
When I ran Rhino as a normal user (with local Admin rights), it was fine.
The issue is Rhino checks to see if there is a service release available.
Rhino uses the same Windows Service for updates that Windows itself does.
Windows is busy using the update service so Rhino can’t.
I think the way it’s supposed to work if the update check is requested and it’s busy, it should fail silently.
For some reason, when I launched Rhino “As Administrator”, (this woas to sort another issue), I got that error.
I get this a lot. Retry will work eventually if you keep trying it.