I received the following message today on one of my production VM’s.

You can use these steps to resolve this issue.

In order to resolve this, you need to use the “consolidate” option within the VM menu.

 

 

According to VMware KB 2003638,

Consolidating snapshots may be required when:

• The snapshot commit fails due to locked files. For details on how to release the lock on locked files, see Investigating virtual machine file locks on ESXi/ESX (10051).
• There is a temporary loss of communication between the vCenter Server and the ESXi/ESX host during snapshot commit. To refresh the connectivity, restart the ESXi/ESX host management agents. For more information, see Restarting the Management agents on an ESXi or ESX host (1003490).