Activate Windows Server: slmgr /ipk and slmgr /ato
To activate Windows Server, install your licence key with slmgr /ipk <key>, then run the online activation slmgr /ato. Check the result with slmgr /xpr. The slmgr utility is built into the system and runs from Command Prompt or PowerShell with administrator rights. Here is the whole process.
What you need
- A valid licence key for your edition (Standard or Datacenter).
- Administrator rights.
- Internet access for online activation (or a KMS server for volume licences).
Step 1. Check the current status
Open PowerShell as Administrator and look at the licence state:
slmgr /xpr
If the system is not activated, you will see a message about evaluation mode or an expired term.
Step 2. Install the licence key
Enter your product key (format XXXXX-XXXXX-XXXXX-XXXXX-XXXXX):
slmgr /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
A confirmation window reports that the key was installed successfully.
Step 3. Run the activation
Activate the system against Microsoft’s servers:
slmgr /ato
On success you get the message “Product activated successfully”.
Step 4. Verify the result
Confirm that activation went through:
slmgr /xpr
The answer “The machine is permanently activated” means everything is correct. For detailed licence information:
slmgr /dlv
Activation through KMS (volume licences)
If you hold a volume licence and have a KMS server, point the system at it and activate:
slmgr /skms kms.example.local:1688
slmgr /ato
Core slmgr commands
| Command | Purpose |
|---|---|
slmgr /ipk <key> |
Install a product key |
slmgr /ato |
Activate online |
slmgr /xpr |
Show activation status and term |
slmgr /dlv |
Detailed licence information |
slmgr /skms <host> |
Set the KMS server |
slmgr /upk |
Remove the installed key |
Frequently asked questions
slmgr /ato returns error 0xC004F074 — what should I do?
That error usually means the activation or KMS server is unreachable. Check the internet connection, the KMS address (slmgr /skms) and time synchronisation on the server.
How do I activate without internet access?
Use phone activation: run slui 4, pick your country and follow the prompts to get a confirmation code by phone.
My key does not match my edition — can I change the edition?
Yes, with a valid key you can change the edition using DISM /online /Set-Edition:<edition> /ProductKey:<key> /AcceptEula.
How does activation differ from extending a trial?
Activating with a key makes the Windows copy permanent and legal for production. Extending a trial with slmgr /rearm is a temporary reset of the evaluation period, for testing only.
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