You cannot open the console of your virtual machines
Opening virtual machine console fails
When accessing the Open Console option from a virtual machine, you see the error:
Unable to get the window handle for the "AxQuickMksAxCTL' control.
To resolve this issue, set the system DEP policy to Always Off in the Windows operating system.
Run a command prompt as administrator
# bcdedit.exe /set nx AlwaysOff
Uninstall the vCenter Server Client(s).
Re-install the vCenter Server Client(s).