Install Microsoft Office 2021 using setup.office.com
How to Install Microsoft Office 2021 Professional Plus
This guide explains how to install and activate Microsoft Office 2021 Professional Plus on a Windows desktop or laptop.
Follow the step-by-step instructions below. If you experience an installation or activation problem, the support information is provided at the bottom of this guide.
Before Installing Office 2021 Professional Plus
We recommend removing previous Microsoft Office versions before installing Office 2021 Professional Plus.
Read our guide: How to uninstall older Office versions .
You should also remove any Microsoft 365 trial version installed on the computer. This may appear in the Windows Start menu as Office. Right-click the application and select Uninstall.
Once previous Office installations and trials have been removed, you can begin installing Office 2021 Professional Plus.
Step 1: Sign In to Microsoft Setup
Open your browser and visit:
Select Get started, then sign in with your Microsoft account. Create a Microsoft account if you do not already have one.
Step 2: Enter Your Office 2021 Product Key
Copy the 25-character product key from your order email.
Place your cursor in the first product-key field and paste the code. The remaining product-key boxes should populate automatically.
Check the key carefully and then select Next.
Step 3: Choose Your Language and Version
Select your country or region and the language you want to use.
You may also be asked whether you want the 32-bit or 64-bit edition. The 64-bit version is suitable for most modern computers unless you specifically need the 32-bit version for compatibility with older software.
Follow the on-screen instructions to begin the download.
Step 4: Open the Downloaded Installation File
The Office installation file should normally download to your Windows Downloads folder.
Double-click the downloaded file to open it and begin the installation.
After approximately 30 seconds to one minute, the Office installation screen should appear.
Step 5: Install Microsoft Office 2021
Installation normally takes around 15 to 30 minutes. The exact time will depend on your computer, broadband connection and Microsoft server availability.
Do not restart or switch off your computer while Office is installing.
Step 6: Complete the Installation
When installation has finished, Microsoft will display a completion message.
Select Close and restart your desktop or laptop.
Step 7: Open an Office 2021 Application
After restarting, search for an Office application such as Word using the Windows search box.
Do not open an application simply labelled Office, as this may be a Microsoft 365 application rather than Office 2021 Professional Plus.
Open Word and select:
File > Account
Check that the installed product is shown as Office 2021 Professional Plus.
If another edition such as Microsoft 365 is shown, remove that installation and repeat the installation process.
Read: How to uninstall older Office versions .
Step 8: Activate Office 2021 Professional Plus
When you open an Office 2021 application, the activation screen should appear.
Copy the product key supplied in your order email and paste it into the product-key field.
Follow the on-screen prompts to complete activation. Once activation is successful, Office 2021 Professional Plus will be installed and ready to use.
Installation or Activation Issues
If you experience a problem while installing or activating a product purchased from Ecokeys, email:
Please include:
- A screenshot of the complete error message.
- A short description of the problem.
- The Windows operating system you are using.
- Your Ecokeys order number.
Our support team will respond during business hours.
Purchase Office 2021 Professional Plus
Office 2021 Professional Plus is available from Ecokeys:
Microsoft Office 2021 Professional Plus licence and download
