Download & Activation Guides

Before you start

• Use your key on the matching edition. A Windows 11 Pro key activates Pro, not Home. An Office Professional Plus key activates Professional Plus, not Home & Business. The edition is written in the product name on your order.
• Always download from Microsoft. Every link below points to microsoft.com. Never install Microsoft software from a third-party file host.
• Be connected to the internet. Activation is a short exchange with Microsoft's servers. If your PC is offline or behind a strict firewall, use phone activation instead.
• Back up first if you are doing a clean install. A clean installation erases the drive you install to.

Download the installation media

Microsoft publishes the installer and ISO for both releases on its own site: the Windows 11 download page and the Windows 10 download page. The Media Creation Tool writes a bootable USB drive for you; the ISO option suits virtual machines.

Activate an installation you already have

1. Open Settings → System → Activation.
2. Select Change product key (or Update product key).
3. Enter the 25-character key from your order email, choose Next, then Activate.
4. The Activation page should now read Windows is activated.

Activate during a clean install

Boot from the USB drive you created, and when Windows Setup asks for a product key, type the key from your order email. Setup then installs the matching edition automatically and activates once you reach the desktop and connect to the internet.

Upgrading from Home to Pro? Enter the Pro key on the Activation page — Windows performs the edition upgrade in place, and your files and apps stay where they are.

1. Go to setup.office.com and sign in with your Microsoft account, or create a free one.
2. Enter the 25-character Office key from your order email and confirm your country and language.
3. The key is now tied to that Microsoft account. Choose Next, then Download to get the installer.
4. Run the installer, then open Word or Excel once so Office signs in and completes activation.

Keep the Microsoft account you used — it is where your licence lives, and it is how you reinstall Office later on the same computer.

Office for Mac

The process is identical: redeem the key at setup.office.com, then download the Mac installer offered there. Office 2021 for Mac runs natively on Apple silicon; Office 2019 and 2016 for Mac suit older Intel Macs.

Volume and LTSC editions

Standard LTSC and Professional Plus volume builds install with the Office Deployment Tool rather than through setup.office.com. If your order includes one of these, the instructions come with your key — and support will walk you through it if you would rather not do it alone.

Windows Server 2025 and 2022

1. Download the ISO from the Microsoft Evaluation Center and install the edition you bought (Standard or Datacenter).
2. Open an elevated Command Prompt and run slmgr /ipk YOUR-KEY to install the licence.
3. Run slmgr /ato to activate against Microsoft, then slmgr /xpr to confirm the licence is permanent.

An evaluation build converts to the full retail edition as soon as a valid key is applied — there is no need to reinstall.

Visio, Project, Access, Word and Outlook

Standalone apps redeem exactly like Office: sign in at setup.office.com, enter the key, download, install, then open the app once to finish activation. If you already have another Office suite installed, install the standalone app afterwards so the two builds match.