UPDATE MAY, 2020. PLEASE NOTE: The instructions below are out of date and no longer appear to be working. See Microsoft’s Windows 10 Activation page. Telephone activation should not be needed for Windows 10 anymore. If you purchased a product key and it’s not activating via the normal methods, there is a real possibility you were sold an invalid license. Return the license to the vendor for a refund if it will not activate, and always purchase Windows 10 either from Microsoft directly, or from a known and reputable vendor.
Please check the official retail pricing for Windows 10. If the price you are being offered is significantly less than this price, you are almost certainly being offered an invalid / illegal license.
If you get an error when attempting to activate your Windows 10 license on the Internet, and you know the license is good and from a legitimate source, there is a way to activate your license using the telephone system instead.
It is important to first attempt Internet activation. Firstly, Internet activation works most of the time, so it’s always worth a try. Secondly, attempting Internet activation stores the product key in Windows which you are trying to activate. In my tests, telephone activation won’t work properly unless the product key is in there. So always try Internet first.
Once you have done so…
- Press the Win+R keys to open Run, then type: SLUI 4, then click on OK.
Note that there is a space between SLUI and 4.
- Select your country or region, then click Next.
- Call the provided phone number to reach the Microsoft Product Activation Center. You will first be walked through an automated menu where you must answer a few questions about what product you are trying to activate (Windows 10), whether you have previously activated it (No), and whether you have a product key (Yes).
- The automated system will now describe the Internet Activation process to you. You already know this information, but simply wait for it to complete. At the end, the system will ask you if you still need assistance. Tell it “Yes”, and then you will be taken to a human operator.
- The human operator will ask confirmation of what product you are trying to activate (Windows 10), and then they will ask you if you have an Installation ID (Yes – it’s on the same screen as the phone number you called).
- The human operator will then ask you to read them that number. I’ve found you can read it to them relatively quickly and they keep up just fine; and if you speak clearly, you usually only have to read it once.
- The human operator will then turn you back over to the automated telephone system, which after a few brief instructions will read your Confirmation ID to you. So once the human operator hands the call back to the automated system, click “Enter Confirmation ID” and type in the numbers when they are read to you.
- Once you have entered the Confirmation ID, you can click Activate Windows and if your product key is valid and the numbers have been typed in correctly, you should be all set.