Parallels Desktop includes an updating feature that helps you keep your Parallels Desktop installation up-to-date. You can use the update feature only if your computer is connected to the Internet.
Update checks can be performed either automatically or manually .
Note: Before updating, you will be asked to quit Parallels Desktop. If you have any virtual machines running or paused, suspend or shut them down. When you start or resume your virtual machines after the update, reinstall Parallels Tools.