Phone Activation Method
1: Right click start menu and choose "Command Prompt (Admin)".
2: Type following script and press Enter.
slmgr.vbs -ipk <Product Key>
4: Select "United Kingdom" from the list below and hit NEXT
5a: Use skype to call the Toll Free Number: +448000188354 as shown in below screenshot
5b: Press 1 when she ask if you are home user
5c: After this she will ask how many computer you activated press 1 (that is Important)
5d: Enter the installation ID one by one
6: After successful confirmation, she will tell you confirmation ID enter it in below boxes and you are done CONGRATULATION!
7: To check the validity
goto command prompt as admin (as you did in step 1)
and copy the following command and hit Enter
slmgr.vbs /xpr