Sometimes the VMware tools need to be restarted in order to get the shared clipboard functionality working again.
From inside a Windows VM, you can do that like this:
net stop vmtools
This will create this output:
The VMware Tools Service service is stopping.
The VMware Tools Service service was stopped successfully.
Then start the service again:
net start vmtools
Giving this output:
The VMware Tools Service service is starting.
The VMware Tools Service service was started successfully.
From outside your virtual machine, you can do it like on this URL using sc: http://www.dailyhypervisor.com/2009/03/25/script-restarting-vmware-tools-remotely/