VSphere | Advanced snapshot trobuleshooting - Part 3 - Example: Invalid snapshot configuration

Unable to consolidate because of invalid snapshot configuration

This is Part 3 of the short tutorial series:
vSphere | Advanced snapshot troubleshooting

This is much more advanced than our previous example.  You will see these two errors if you attempt to consolidate, clone or migrate the VM:

Detected and invalid snapshot configuration

or

... vmdk was not found

VSphere | Advanced snapshot trobuleshooting - Part 2 - Example: Unable to consolidate because the file is locked

This is Part 2 of the short tutorial series:
vSphere | Advanced snapshot troubleshooting

Virtual Machine consolidation attempts result with bellow error:
Unable to access file since it is locked

VSphere | Advanced snapshot trobuleshooting - Part 1 - The ESXi shell is your friend

I am writing this article as an extension to my previous post A VM is showing disk size of 0B where I will attempt to make a general explanation on how to troubleshoot and successfully solve snapshots and consolidation problems in your vSphere with a number of examples. Because the general article was so big, I decided to split it into three parts. This Part 1, is where I am describing the commands which are used to solve most of the snapshot problems and in the next two parts I will describe the process of troubleshooting via examples.

vSphere | Virtual Machine that is neither powered on nor powered off

I had a very interesting problem with a VM for which I concluded being in a phantom state, that is a VM that is neither powered on, nor powered off. No matter what you try to do to the VM you always end up with error message that says:

The attempted operation cannot be performed in the current state: Powered ON.

The thing is, that if you try to access the console, the machine is not powered on. Even more, if you open the VMRC you could end up seeing an error message:

Unable to connect to the MKS: The operation is not allowed in the current state.

So what should I do? I decided to hit the ESXi Shell. VMware has a pretty nice KB article and even a video on what to do when you encounter this problem:

ESXi 5.5 | KB 1014165

Connect to the host using an SSH client and try the steps described into that article. However if the VM still cannot be powered off than you must reboot the ESXi host in order to refresh the VM state.

If this happens too often then you must consider moving everything off that host, as this probably indicates problems with the host itself.

vSphere | A VM is showing disk size of 0B

Being given a task to figure out and clean up the mess of a poorly maintained vSphere Infrastructure a while ago, i encountered a very strange problem.

They informed me that the Veeam Backup failed for that VM, and the error message was:

Virtual disk configuration change detected, resetting CBT failed Details: A general system error occurred: 
Creating VM snapshot
Error: A general system error occurred: