Symptoms

After successful installation of Windows into Parallels Virtual Machine, Windows prompts for activation or displays that it is not genuine.

Cause

If you're seeing notifications that the copy of Windows that is installed on your Virtual Machine might not be genuine, or that you might be a victim of counterfeit software, it's likely that your copy of Windows was not properly activated or not genuine.
You'll receive periodic reminders that Windows is not genuine until you activate Windows. In addition, to more clearly display these messages, your desktop might turn black. You can reset it, but every 60 minutes, it will return to black until the issue is resolved. Regardless of genuine status, Windows will be able to get critical security updates. However, access to optional updates or benefits available exclusively to genuine Windows customers, such as Microsoft Security Essentials, might be restricted.

Resolution

To fix this, click the notification and follow the steps to either repair Windows or — if you have inadvertently obtained counterfeit software — buy genuine Windows.

1. Start Parallels Desktop application and Windows virtual machine

2. Go to Control Panel ► System ► Activate now ► Activate online.

   

   

If Windows is not activated, please proceed to the following steps:

1. In the activation wizard click on the Show me other ways to activate ► option Activate through phone

   

2. Enter the digits displayed on the screen and Call Microsoft on the given number based on the geographical location.
3. Inform Microsoft support that you have installed Windows OS successfully in the virtual machine but have not succeeded in activating it.

4. Microsoft Support would activate this Windows OS now for you remotely.

   For more information about genuine Windows, please refer to Microsoft FAQ.