How to Install and Activate Microsoft Office 2024 on Windows and Mac

You have just purchased a Microsoft Office 2024 product key and you want to get up and running as quickly as possible. Whether you are installing on a brand-new Windows PC or a Mac, this step-by-step guide covers every stage of the process—from redeeming your key to troubleshooting common activation errors.

The entire installation typically takes between five and fifteen minutes, depending on your internet speed. Let us walk through it.

Before You Begin: What You Need

• A valid Microsoft Office 2024 product key (25 characters, formatted as XXXXX-XXXXX-XXXXX-XXXXX-XXXXX)
• A Microsoft account (free to create at account.microsoft.com)
• A stable internet connection (the installer downloads approximately 4 GB)
• Windows 10/11 or macOS Monterey (12) or later
• At least 4 GB of available disk space

Important: Make sure you know which edition you purchased. Office 2024 Home & Student, Home & Business, and Professional Plus each have different installers. Your product key will only work with the correct edition. If you purchased from Softkeys.uk, your confirmation email specifies the exact edition.

Part 1: Installing on Windows

Step 1 — Sign In to Your Microsoft Account

Open your web browser and navigate to setup.office.com. Sign in with your Microsoft account. If you do not have one, click "Create a new account" and follow the registration steps. Use an email address you will remember—your Office licence is permanently linked to this account.

Step 2 — Redeem Your Product Key

Enter your 25-character product key in the field provided. Double-check each group of five characters; the most common entry errors involve confusing the letter O with the number 0, and the letter I with the number 1. Click "Next" to redeem.

Step 3 — Select Your Region and Language

Choose "United Kingdom" as your country/region and "English (United Kingdom)" as your language. This ensures that default spelling, date formats, and currency symbols are set to British standards. Click "Next."

Step 4 — Download the Installer

Click "Install Office" to download the setup file (OfficeSetup.exe). The file is small—around 7 MB—because the full suite is downloaded during installation.

Step 5 — Run the Installer

Locate the downloaded file (usually in your Downloads folder) and double-click it. If Windows asks "Do you want to allow this app to make changes to your device?", click "Yes." The installer will begin downloading and installing Office applications. You will see a progress bar; do not turn off your computer or disconnect from the internet during this process.

Step 6 — Launch and Activate

Once installation is complete, open any Office application (Word is the easiest choice). You will be prompted to sign in with your Microsoft account—use the same account you used to redeem the key. Office will activate automatically. You should see "Product Activated" in File → Account.

Part 2: Installing on Mac

Step 1 — Redeem Your Key

Visit setup.office.com in Safari or any browser. Sign in with your Microsoft account and enter your product key, exactly as described in the Windows instructions above.

Step 2 — Download the Installer

After redeeming, click "Install Office." macOS will download a .pkg installer file (approximately 1.8 GB for the full suite).

Step 3 — Run the Installer

Open the downloaded .pkg file. Follow the on-screen prompts: agree to the licence terms, select your installation drive (the default is usually correct), and click "Install." You may be asked to enter your Mac's admin password.

Step 4 — Activate

Open any Office app from Launchpad or the Applications folder. Click "Sign In" and enter your Microsoft account credentials. Activation happens automatically. Confirm by checking the licence status under the application's About menu.

Troubleshooting Common Activation Issues

Error: "This product key has already been used"

This usually means the key was previously redeemed to a different Microsoft account. Check whether you have another Microsoft account where you may have already entered the key. If you are certain you have not used the key, contact the retailer for a replacement. At Softkeys.uk, we provide free replacements for any key that fails to activate.

Error: "This product key is not valid"

Double-check for typos. Common mistakes include confusing 0 (zero) with O (letter), 1 (one) with I (letter), and 5 with S. If the key still does not work after careful re-entry, contact support.

Error: "We can't verify your product key"

This can occur if Microsoft's activation servers are experiencing temporary issues. Wait 30 minutes and try again. If the problem persists, try activating via phone: open any Office app, go to File → Account → Activate by Phone, and follow the automated prompts.

Office Installed but Not Activated

Open any Office app, go to File → Account, and click "Activate Product." Sign in with the Microsoft account you used to redeem the key. If you see "Subscription Expired" or "Unlicensed Product," you may be signed in with the wrong account.

Installation Freezes or Fails

1. Temporarily disable your antivirus software (re-enable it after installation).
2. Ensure you have at least 4 GB of free disk space.
3. Try a wired internet connection instead of Wi-Fi if the download keeps failing.
4. Use the official Microsoft Support and Recovery Assistant to clean up any partial installations, then retry.

Post-Installation: Essential First Steps

Update Office

After activation, check for updates immediately. In any Office app, go to File → Account → Update Options → Update Now. This ensures you have the latest security patches and bug fixes.

Set Your Preferences

Configure your default save location, theme (light, dark, or system-matched), and accessibility settings. In Word, set your proofing language to "English (United Kingdom)" to use British spelling by default.

Link OneDrive (Optional)

If you want to save documents to the cloud, sign in to OneDrive with the same Microsoft account. This is particularly useful for accessing your files across devices. Note that Office 2024 does not include bonus OneDrive storage; you get the standard 5 GB free tier.

Save Your Product Key

Store your product key in a safe place—a password manager, a secure note, or even a printed copy in a filing cabinet. You may need it again if you reinstall Office or move it to a new computer.

How to Transfer Office 2024 to a New Computer

1. On your old computer, go to File → Account and note the Microsoft account associated with the licence.
2. Uninstall Office from the old machine via Settings → Apps → Installed Apps.
3. On the new computer, visit account.microsoft.com/services and sign in.
4. Find your Office 2024 licence and click "Install."
5. The licence transfers automatically. No new key is required.

Frequently Asked Questions

Can I install Office 2024 on more than one computer?

A single retail licence covers one PC or Mac. To install on additional devices, you need additional licences. At Softkeys.uk, Office 2024 Professional Plus is just £29.99 per licence.

Do I need an internet connection to use Office after installation?

No. Once activated, Office 2024 works entirely offline. An internet connection is only required for the initial download, activation, and periodic security updates.

What happens if I format my hard drive?

Your licence is tied to your Microsoft account, not your hard drive. After reinstalling Windows or macOS, simply download Office again from your account page and sign in to reactivate.