Office 2021 Pro Plus – Download, Install & Activation Guide (All Languages)

Microsoft Office 2021 Professional Plus is the latest perpetual-licence version of Microsoft's flagship productivity suite. This complete guide covers everything you need: official ISO download links in every language, step-by-step installation instructions, all activation methods (product key and phone activation), system requirements, and where to get a genuine Office 2021 Pro Plus key at the best price.

Office 2021 Pro Plus is a one-time purchase with no monthly subscription. It includes Word, Excel, PowerPoint, Outlook, OneNote, Teams, Publisher, Access, and the full suite of Microsoft productivity tools — upgraded with co-authoring, new Excel functions, and performance improvements over Office 2019.

⬇ Download Office 2021 Pro Plus ISO (English) 🔑 Buy Office 2021 Pro Plus Key – from $28.99

What Is Microsoft Office 2021 Professional Plus?

Microsoft Office 2021 Professional Plus is the most complete one-time-purchase version of the Office suite, released in October 2021 alongside Windows 11. It delivers the features that were added to Microsoft 365 between the Office 2019 and October 2021 releases, including real-time co-authoring, new Excel functions (XLOOKUP, LET, XMATCH), dark mode across all apps, improved accessibility tools, and Microsoft Teams integration.

It is designed for professionals, businesses, and power users who prefer a perpetual licence over a subscription and want the latest features without ongoing fees.

Office 2021 Pro Plus – System Requirements

Step 1: Download Office 2021 Pro Plus ISO – All Languages

Microsoft provides official Office 2021 Pro Plus ISO files directly from their CDN in every language. Click the link for your language below to start the download. The files are in .img format — rename to .iso if needed, or use Windows’ built-in mount function directly.

Step 2: Install Office 2021 Professional Plus

1. Mount or Extract the ISO File

Right-click the downloaded .img file and select Mount (Windows 10/11 support this natively). A virtual drive will appear in File Explorer. If your system doesn't recognise the .img format, rename it to .iso first.

2. Run Setup.exe

Open the mounted drive and double-click Setup.exe. Click Yes if prompted by User Account Control. The Office installer will launch and begin downloading additional components.

3. Wait for Installation to Complete

The installation typically takes 10–20 minutes. Office will install all Pro Plus applications automatically: Word, Excel, PowerPoint, Outlook, OneNote, Teams, Publisher, and Access. You do not need to select individual apps.

Step 3: Activate Office 2021 Professional Plus

Method 1: Product Key Activation (Recommended)

1. Open any Office app (e.g. Word, Excel)
2. Click File → Account
3. Under Product Information, click Activate Product
4. Enter your 25-character Office 2021 Pro Plus product key
5. Click Next and follow the prompts — activation is instant and online

Method 2: Activate via Command Prompt (Slmgr)

1. Open Command Prompt as Administrator
2. Navigate to the Office installation folder: cd "C:\Program Files\Microsoft Office\Office16"
3. Run: cscript ospp.vbs /inpkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX (replace with your key)
4. Then run: cscript ospp.vbs /act
5. You should see: Product activation successful

Method 3: Phone Activation

If online activation fails (e.g. the key was previously used or you're offline), you can activate by phone:

1. Open an Office app and go to File → Account → Activate Product
2. When prompted, choose “I want to activate the software by telephone”
3. Select your country to get a local Microsoft activation number
4. Call the number and provide the Installation ID shown on screen
5. Microsoft will give you a Confirmation ID to enter and complete activation

Office 2021 Pro Plus – Key New Features vs Office 2019

Buy a Genuine Office 2021 Pro Plus Key

Softkeyworld supplies authentic Microsoft Office 2021 activation keys with instant email delivery and a 7-day refund policy.

🔑 Buy Office 2021 Pro Plus Key – from $28.99

Frequently Asked Questions

Q1: Is Office 2021 Pro Plus a one-time purchase?

Yes — Office 2021 Professional Plus is a perpetual licence. You pay once and use it forever on one PC. There are no monthly fees unlike Microsoft 365.

Q2: What is the Office 2021 Pro Plus build number?

The RTM (release to manufacturing) build is v2108, Build 14332.20198. The widely-cited build office_pro_plus_2021_v2109_build_14430.20276 is a later cumulative update released shortly after launch.

Q3: Can I download Office 2021 ISO in my language?

Yes — see the language download table above. Simply click the link for your language to download the official ISO directly from Microsoft's CDN.

Q4: Does Office 2021 work offline?

Yes — all core Office 2021 applications (Word, Excel, PowerPoint, Outlook, etc.) work fully offline. Internet is only required for initial activation and for cloud-connected features like OneDrive sync.

Q5: Will Office 2021 receive updates?

Office 2021 receives security patches only (no new features) until its end of support in October 2026. For continuous feature updates, you would need Microsoft 365.

All ISO download links point directly to Microsoft’s official Content Delivery Network (officecdn.microsoft.com). Softkeyworld supplies genuine Microsoft activation keys with instant email delivery and a 7-day refund policy. Registered in England and Wales, Company No. 13321373.