Windows Server editions (2012 R2, 2016, 2019, 2022 and 2025) are activated by phone, using an Installation ID and a Confirmation ID. This guide shows you how to do it with a couple of quick commands — it only takes a few minutes.
How to Activate Windows Server by Phone
- Open Command Prompt as administrator and install your key by typing:
slmgr.vbs /ipk YOUR-KEY
(replaceYOUR-KEYwith your product key). - Press Windows + R, type slui 4 and press Enter.
- Select your country/region and click Next — you’ll be shown a 63-digit Installation ID.
- Enter that Installation ID in the tool below — along with your order number, order email and product type — to get your Confirmation ID:
Finishing Activation
Enter the Confirmation ID the tool gives you back into the phone-activation window and click Activate Windows — your Windows Server will be activated.
Trouble Activating?
If you run into any problem, open a support ticket and we’ll help during working hours. Every key includes a 7-day warranty, so reach out within the warranty period and we’ll send a fix or a new key.
Where to Buy a Genuine Windows Server Key
Need a key? Browse our genuine Windows Server keys — Datacenter, Standard and Essentials editions from 2012 R2 to 2025 — delivered instantly on your order confirmation page.
Frequently Asked Questions
Which Windows Server versions does this work for?
Windows Server 2012 R2, 2016, 2019, 2022 and 2025 — Datacenter, Standard and Essentials.
What does the slmgr.vbs /ipk command do?
It installs your product key. The slui 4 command then opens the phone-activation window where you enter your Confirmation ID.
Is this a genuine Microsoft key?
Yes — every key is genuine and activates directly with Microsoft.
What if I get an activation error?
Open a support ticket within your 7-day warranty and we’ll send a replacement key or a fix.