VMware tools provides a copy and paste function between the machine running the vSphere client and the guest virtual machine.
In some production environments this maybe inappropriate.
It is possible to disable this feature on a per virtual machine basis, by editing the guest Virtual machine configuration (vmx) file.
1. Log into your vCenter client
2. Power off the guest Virtual machine.
3. Open the guest machine advanced options ( click Edit Settings > Options > General > Configuration Parameters )
4. Add the following parameters (click Add Row),
isolation.tools.setGUIOptions.enable = false
isolation.tools.copy.disable = true
isolation.tools.paste.disable = true