When using a Volume Activation Management Tool ( VAMT ) 3.1: The specified KMS product key is invalid, of is unsupported by this version of VAMT. An update to support additional products may be available online. When adding Windows 10 product keys.

When you receive this error while trying to import your Windows 10 product keys to KMS VAMT server 3.1, the only way is to upgrade your VAMT version.

It is not possible to import Windows 10 keys in VAMT 3.1 keys.

Download the software from Microsoft:

https://msdn.microsoft.com/en-us/library/windows/hardware/dn914754%28v=vs.85%29.aspx?f=255&MSPPError=-2147217396

https://msdn.microsoft.com/en-us/windows/hardware/dn913721.aspx

Direct download :

http://go.microsoft.com/fwlink/p/?LinkId=526740

run setup and install SQL Express and VAMT.