Shared clipboard stops working on VirtualBox

Shared clipboard stops working between guest to host. It begins working fine but at a given time stops. My solution was restart VM, but looking into the problem it is related with VBoxTray program. My environment is:

• VirtualBox 4.1.8
• Host Ubuntu
• Guest Windows XP

The problem is inside the guest, to fix it is enough to stop VBoxTray program and start again. Bellow a little script to restart the service when clipboard is not working:

@echo off

taskkill /F /T /IM VBoxTray.exe

start VBoxTray.exe

exit

Put this code in a cmd and throw it when the problem occurs.