Method 1
Must Read: Before installing Office 2021, you must prepare your computer. It is strongly recommended to have only one Office installed on your computer. So, before starting the installation process, it is very important to uninstall all previously installed Office versions: Office 2013, Office 2016, Office 365 or Microsoft 365 trial versions, etc. For more information: Click here to view Microsoft reference kb article to uninstall a program.
Installation
- Step 1: Go to www.office.com/setup for Office Setup.
Select the Office product you want to install by going to www.office.com/setup in your browser. - Step 2: Sign In to your Microsoft Office Account
To complete the purchase and set up an office, log in to your account at www.office.com/setup. You’ll need to make a Microsoft Account if you don’t already have one.
Red Box 1. Log in to your account at www.office.com/setup. You’ll need to make a Microsoft Account if you don’t already have one.
Red Box 2. If you have redeemed our license before, you need to login your Microsoft account and re-download and install.
- Step 3: Enter your Microsoft Office Product Key
You’ll need to enter the Product key in the orange area if you’ve opened your account or created a new one. Choose your country and preferred language.
- Step 4: Download and Install Office
You can begin downloading the software once you have entered all the correct information. Follow the on-screen instructions to begin downloading your registered Microsoft Office photocopy. - Step 5: Run the Activation wizard
After you’ve started the office installer, follow the on-screen instructions that appear on the screen. Now, all we have to do is wait for the office setup to complete the installation process. - Step 6: Open and Run office Applications
When you open any Office app once the installation is complete, you will see a welcome screen with the message “You’re All Set” and the office will be activated.
Method 2 ( Recommended )
1. Preparation
Before you install Office 2021, before starting the installation process, it is very important to uninstall all previously installed Office versions: Office 2013, Office 2016, Office 365 or Microsoft 365 trial versions, etc. You may refer to this help document from Microsoft in case you need assistance with this step.
2. Downloading
Choose your language and click the link to download the ISO/IMG file. The download process should start after clicking the link. After downloading, we will explain how to finally install Office 2021.
Here is a list of Microsoft official links to download the Office 2021 Professional Plus ISO file.
Choose your language, click the link to start the download and wait for the download to finish before mounting the file. It can take 10-20 minutes depending of your internet speed.
You can follow the download progress on your browser using the shortcut CONTROL+J
WORKS IN MOST OF THE BROWSERS: CHROME, FIREFOX, EDGE, OPERA…
3. Installation
- Mounting ISO file
To install Office 2021, access your Downloads folder to locate the downloaded ISO file and right-click on the ISO file and select the option mount from the contextual menu. See the screenshot below. This will mount the file as a virtual device and allow you to access it like a pen drive.
- Installing
After doing this step, on the left side of this same window, you will see that an Office device appears under This Pc. Click on the new device (1), and then in the right side of the window you will see the content. Finally, double-click on the setup file. You can see it in the screenshot above as the number (2). This will start the installation process.
The installer will choose the best Office version for your computer. However, you may need the 64-bit installation. You can force the 64-bit installation accessing the Office folder and running the file named Setup64.
4. Activation
After completing the installation process, reboot your operating system. When done, start one of the Office applications (Word, for example). After some seconds a new window will popup asking to enter the product key. Enter your product key and click the Activate Office button.
If you receive an activation prompt, please select:
“I want to activate the software over the Internet (recommended).”
However, if you encounter a “maximum activation limit” error, it may be due to Microsoft’s online activation service being temporarily busy or an error from Microsoft’s activation server
In such cases, please choose the optional method:
“I want to activate the software by telephone.”
Then, carefully follow the on-screen instructions to complete the activation. This method is reliable and often resolves the issue when online activation is not successful.
That’s all. Now you have your Office 2021 completely installed and activated. Enjoy your Office suite.
TROUBLESHOOTING
1. “This product key has already been used” error in Office
If you see the error This product key has already been used when you enter your product key on www.office.com/setup or Microsoft365.com/setup, this means your product key has already been redeemed and is no longer needed. Instead, use your Microsoft account to sign in to account.microsoft.com and re-install your Office product.
2. “Office (64-bit or 32-bit) couldn’t be installed” error when trying to install
3. How to fix Error “Couldn’t Install Office”
If Office Error “couldn’t install” is not fixed in registry repair, SFC scan and firewall/antivirus exception, it is required to remove the Office suite completely from the programs and features, and then to reinstall the product for a proper use.
Follow the steps given below to fix Office Error “couldn’t install” completely.
Step 1. Open control panel
Step 2. Click on uninstall programs and features
Step 3. Search for Microsoft Office in the list.
Step 4. Select Microsoft Office and click on uninstall.
Step 5. Once uninstall is finished, try running Office setup to install Microsoft Office.
For more information: Click here to view Microsoft reference kb article to uninstall a program.