How to solve Failed-Activating Windows in AWS EC2

Sometimes when I create a Windows EC2 Instance from one of my custom AMIs I get an activation failed Windows Server.

Follow the instruction below to Activate your Windows Instance. (For Windows Server 2016, 2019 and later only).

Activate Windows Manually using EC2Launch initialization script

Open Powershell on your Windows Server and run the command below.

C:\ProgramData\Amazon\EC2-Windows\Launch\Scripts\InitializeInstance.ps1; cscript "${env:SYSTEMROOT}\system32\slmgr.vbs" /ato

Notes:

  • No need to run Powershell in administrator mode.
  • No need to restart your instance. Once you run the above command, the Activate Windows on your desktop will disappear.
  • This will not update the local Administrator password

There are other ways to Activate Windows on your AWS EC2. You can check them all here.