Virtual machine that appears as invalid for VMware ESX and ESXi

Open the vSphere Client, select the virtual machine wich is in invalid state

1. Right-click the virtual machine and choose Remove from Inventory.
   Caution: Do not choose Delete from Disk.
    
2. Click on the ESX host and, using the Summary tab, locate the appropriate datastore in which the virtual machine exists.
3. Right-click the datastore and click Browse Datastore.
4. Browse to the directory of the virtual machine.
   
   Note: If you have renamed the virtual machine in the VMware Infrastructure Client, use the original name given to it.
    
5. Right-click the .vmx file of the virtual machine and choose Add to Inventory.
6. Power on the virtual machine.

Rename a vmdk with vmkfstools

Delete a Virtual machines appear as invalid with SSH

1. Log in ESXi with SSH
2. Open /etc/vmware/hostd/vmInventory.xml with vi, delete the revelent entry.
3. restart the Management agents in ESXi by issue command /etc/init.d/hostd restart