Failure Configuring Windows Updates. Reverting Changes. Do not turn off your Computer.

The got the below error message when automatic Windows update was running in a Windows 7 which was running in a parallels VM in mac.

"Failure Configuring Windows Updates. Reverting Changes. Do not turn off your Computer."

There could be various reasons for this error to come up. You can google for this and find many reasons. For me, it was a specific one. I found the solution in some blog/forum, but I cannot find that one now, so thought of adding that to my blog.

Reason: 
There was an external hard disk attached to the machine.

Fix:
Remove the external devices and restart the Windows.

Feel free to point out if anything is missing/wrong in this blog. 

You are running VMware Player through an incompatible hypervisor.

Recently I tried to run a VMWare image inside a Windows VM which is running on a Parallels in a Macbook Pro.

I accessed the Windows VM from mac using Parallels. Then I tried to access a VMWare image from the Windows using a VMWare Player. When I tried to run the VMWare Image, I got the below error:

"You are running VMware Player through an incompatible hypervisor.  You cannot power on a virtual machine until this hypervisor is disabled."

Fix:
Open the .vmx file in a text editor and add the below line at the end.

 vmx.allowNested = "TRUE"  

Ref: VMWare Community: Running Nested VMs

Feel free to point out if anything is missing/wrong in this blog.