To enable this option for all the virtual machines in the ESX/ESXi host:

 1.  Log in to the ESX/ESXi host as a root user and open the /etc/vmware/config file using a text editor.
 2.  Add these entries to the file:

isolation.tools.copy.disable="FALSE"
isolation.tools.paste.disable="FALSE"

 3.  Save and close the file.

The Copy and Paste options are only enabled when the virtual machines restart or resume the next time or shutdown and power-on the VM for changes to take effect
Note: These options do not persist after an upgrade. If you upgrade to a newer version after enabling these options, the changes are lost and you may have to re-enable them.