Server 2012 Cannot find C: Boot to cd
Your partition/disk got removed (within ESX) as your list disk within diskpart find nothing.
Check your hardware. A human error that removed the partition, or just unplugged it maybe if lucky. (or a storage array error at your esx level)
Sorry to the user that attempted to answer they question but unfortunately you are both incorrect.
I was actually able to fix the issue and completely forgot about the question here.
I had to call VMware, turns out we were on a older version of vcenter and had to upgrade, had to pay the licensing cost and get the version that supported vAPPS, go through a very long migration process, get everything over to the new systems and decomm/reuse the clusters one by one to get the all over.
I couple hours of downtime later and not so happy CIO we were able to get everything setup and able to change the admin password through vcenter.
All this because the server owner forgot his password.
The reason we went through all this for one server is to be able to not have to go through this again in the future.
Click on the VM, click "Edit Settings". There should be a Hard Drive shown. If it's greyed out or there is no Hard Drive there, then that is why it can't be seen. If it's simply missing, you can add it back by selecting Add... and Hard Drive. Select Next and when it asks if this should be new or existing, select Existing. Browse your datastores for the folder your VM is in and attach the VMDK. Should be good to go after that.
If a snapshot was corrupted, this could also cause a problem with accessing the disk. If the HDD is there, but is showing mounted as /vmname-000001.vmdk or something like this, it is a snapshot and if it is missing from your VMX file, this might be the problem as well. If so, you'll likely need to restore from backup or call VMware.