Export jobs failing with error "The object 'vim.VirtualMachine:vm-######' has already been deleted or has not been completely created" (4368855)

Export jobs failing with error "The object 'vim.VirtualMachine:vm-######' has already been deleted or has not been completely created"

New or existing export or virtual standby jobs are suddenly failing with the following error message:

The object can't be found on the vCenter Server database.

The way to handle this problem is by restarting the Core Service to re-establish the communication with the virtual environment. Information between the backup and virtual systems will be updated. Restarting the service is enough; there is no necessity of rebooting the system. If the Core cannot be restarted at the moment because there are jobs pending, re-schedule the restart for another time.