The full message usually reads "The Software Licensing Service reported that the computer could not be activated. No Key Management Service (KMS) could be contacted." Windows is trying to activate against a company-style KMS server that is not reachable from your PC.
Why it happens
This error is specific. The common causes are:
- The system date and time are wrong. Activation fails when the clock drifts far enough, because the secure connection to the activation service breaks.
- Something is blocking the connection. A VPN, a proxy or a strict firewall can stop Windows from reaching the activation service.
- The PC is set up to look for an organization's KMS server. This happens on computers joined to a company domain, or that were configured for one before.
How to fix it
1. Correct the date and time
Go to Settings > Time & language > Date & time, turn on automatic time, and check the time zone as well. Restart and try again.
2. Remove anything between your PC and Microsoft
Disconnect any VPN or proxy, activate, then reconnect.
3. Force an online activation
Open Command Prompt as administrator and run slmgr /ato. It shows the exact error the service returns, which says more than the message in Settings.
4. If the PC is on a company domain
A domain-joined PC may be pointed at an internal KMS server that will not accept a single-PC key. Your IT administrator can tell you.
If none of this works
Write to us with this code, the result of slmgr /ato and your order number, from our contact page. A key that does not activate is covered by our Lifetime activation guarantee, and support is available 24/7.
