The Copy and Paste options are only enabled when the virtual machines restart or resume the next time or shutdown and power-on the virtual machine for changes to take effect. This must be done on the virtual machine side, not the guest operating system side.
Note: These options do not persist after the host upgrade. If you upgrade to a newer version after enabling these options, the changes are lost and you may have to re-enable them.
For more information, see theLimiting Exposure of Sensitive Data Copied to the Clipboardsection in theESX Configuration Guide.