I have this happening on a couple of computers.
Windows Automatic Updates are set for Friday 3 am.
Every boot the wuauserv runs no matter what.
If the user logged on is a Power User the svchost that wuauserv is in eats 98 to 100% CPU cycles for 5 to 10 minutes and then lets go.
At some point later (5 minutes to 2 hours) wuauserv tries again. This happens every day not just Friday.
If I log on as an Administrator the Windows Update still runs, finds nothing and quickly disappears.
If set for Friday why is wuauserv trying to run on every boot / reboot.
I have killed several processes out of this svchost (Wireless Zero, Windows Time, TCP/IP NetBIOS Helper, Remote Registry) and I have set to “Manual” Machine Debug Manager and DNS Client. All of this was a test and I still am at square one.
