Installing Parallels Tools
Parallels Tools is a collection of utilities and drivers that vastly improve the virtual machine performance and enable some features that are not available otherwise. Parallels Tools are included with every copy of Parallels Desktop and are highly recommended to be installed in every virtual machine right after an operating system is installed in it. Your source virtual machine should have Parallels Tools installed. For instructions on how to install Parallels Tools, please see https://kb.parallels.com/en/115835.
Preparing Windows for mass deployment
When you want to distribute pre-configured Windows virtual machines to your user base, you may need to manage those machines granularly: enroll them into domains, activate Windows licenses, differentiate PC names, enforce specific policies, enable company-wide licensing tools, etc. All that and more can be achieved with the help of Microsoft's Sysprep utility. To learn more, refer to this article.