How to Install and Activate Office: Step-by-Step Guide

Just received your Office product key and want to install it quickly? This guide walks you through a few simple steps: get ready, download Office, install it, activate it with your key and check that everything is in order. Allow about ten minutes in total. The method is the same for the perpetual versions Office 2019, 2021 and 2024.

Before you start

Get these few things ready and you will save time:

• A PC running Windows 10 or Windows 11.
• An Internet connection (needed for the download and the activation).
• Your 25-character product key, received by email.
• If an older Office version is present, plan to uninstall it to avoid conflicts.

Step 1: install Office

Before activating, you need to install the suite on your PC.

1. Sign in to your Microsoft account on Microsoft's official site (or use the media supplied with your license).
2. Start the download of the Office installer that matches your version. The 64-bit version is usually offered by default.
3. Open the downloaded file and let the installation run to the end (a few minutes depending on your connection). Do not close the window before it finishes.
4. Once the installation is complete, open an application, for example Word or Excel.

Step 2: activate with your product key

The first time you open an Office application, you are prompted to activate the product.

1. In the open application, choose the option to activate with a product key (not the sign-in to a subscription).
2. Enter your 25-character product key. Easiest: copy and paste the key received by email to avoid typos.
3. Confirm: activation happens online in a few seconds.
4. Accept the license agreement if prompted. Your suite is ready to use.

An Internet connection is required for this step only. After activation, Office then works offline, with no subscription.

Step 3: check the activation

To confirm that your license is active:

1. Open Word (or another Office application).
2. Go to File, then Account.
3. Under Product Information, you should see the note stating that the product is activated.

If the note confirms activation, you are done: your valid license is in place and usable on this PC. You can close and reopen Office whenever you like, the activation stays recorded.

Activation failing?

In most cases activation goes through without a hitch. If it fails, the most common causes are:

• A mistyped key (confusing I, l and 1, or extra spaces): copy and paste the key.
• An installed Office version that does not match the key (for example a 2021 key on Office 2019).
• No Internet connection at the moment of activation.

For the full list of error codes and complete solutions, see our guide Office activation problems: quick solutions.

Reinstalling Office later

Keep your product key in a safe place. If you format your PC or reinstall Windows, you can reinstall Office on the same computer and reactivate it with the same key, by starting this guide again from step 1.

What about security updates?

Once activated, your Office version receives security and reliability updates for as long as it is supported by Microsoft. Office 2024 is supported the longest (until October 2029), Office 2021 until October 2026, and Office 2019 reached end of support in October 2025. The major new features of Microsoft 365 are not added: a perpetual license keeps the applications of its version, with no subscription or recurring fees.

Need an Office product key?

If you do not have your license yet, the most recent and best-supported version is Office 2024 Professional Plus, with the key delivered by email. Depending on your budget, you can also choose Office 2021 Professional Plus or Office 2019 Professional Plus. Once you receive the key, just start this guide again from step 1.