Use a Multiple Activation Key (MAK) instead of KMS activation

If KMS activation will not be used, and if there is no KMS server, the product key should be changed to a MAK. For Microsoft Developer Network (MSDN) the stock-keeping units (SKUs) that are listed below the media are usually volume licensed-media, and the product key that is supplied is an MAK key.
Change the product key to a MAK. To do this, follow these steps:

1. Open an elevated Command Prompt
2. If you are prompted for an administrator password or for confirmation, type the password or provide confirmation.
3. At the command prompt, type the following command, and then press Enter:

slmgr -ipk xxxxx-xxxxx-xxxxx-xxxxx-xxxxx

Note In this command, the placeholder xxxxx-xxxxx-xxxxx-xxxxx-xxxxx represents your MAK product key.

4. Next type the following commands:

slmgr.vbs /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

slmgr.vbs /ato

The first command will update the key.

The second command will activate Windows.