Hanging Blank Desktop - WMI?

Recently, about every 1 in 3 or 4 times that I boot up my computer, Windows (7 Ultimate, no SP1) goes through the normal startup screen, but upon arriving at the desktop, no icons/Explorer/taskbar appear, nor does the cursor- it's almost completely frozen, just showing the desktop background. The only response I can get is via Ctrl+Alt+Del, which just brings me to a black screen, and Esc brings me back to the blank desktop, that's it. I don't have to hard reset to shutdown, if I just press the power button once, the desktop will fade to black (like a normal shutdown), and just turn off correctly (no unexpected shutdown messages or Kernel Power errors) after a while. It seems to be occurring increasingly often.I have not seen the problem occur in safe mode- however, because the problem does not occur every time, it could just be that I've only booted in safe mode on occasions when it wasn't going to do it.Looking at Event Viewer, the most consistent error I get in relation to this is WMI Event 10:

"Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected."Now, for this error, obviously the online help for that event suggests that the fix is to update permanent event subscriptions with the WMI Event Registration tool, but I'm very unfamiliar with WMI and such things, and while I'm sure I could figure it out given time, I'd rather solve this sooner rather than later, and I'm not getting anywhere with that program. Additionally, I ran WMI Diag, which came up with a large number of errors.

Other possibly related errors include:Event 1002 (though this is described as an unimportant, self-fixing error, which I can confirm, but it continually reappears, even though it's being fixed in between): The IP address lease 10.1.1.7 for the Network Card with network address 0x001F337767D6 has been denied by the DHCP server 10.1.1.1 (The DHCP Server sent a DHCPNACK message).Event 7001: The Network List Service service depends on the Network Location Awareness service which failed to start because of the following error: The dependency service or group failed to start.Event 11: The driver detected a controller error on \Device\Harddisk7\DR7.

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