How to activate Microsoft Office 2021 Professional Plus — activation instructions

Methods of activating Office 2021

After installing the Office 2021 Professional Plus package, you must activate it with a product key from KluczeSoft. Below, you will find 3 methods of activation.

Method 1: Through the Office interface (recommended)

1. Launch any application — e.g. Microsoft Word
2. If the welcome screen appears, click Blank document
3. Go to File → Account (in the bottom left corner)
4. Click Change product key
5. Enter the 25-character key from KluczeSoft (format: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX)
6. Click Activate Office package
7. If a question appears — select Activate by Internet

After successful activation, in the Account section, you will see: Product activated and the name Microsoft Office LTSC Professional Plus 2021.

Tip: If the "Change product key" button is not visible, close all Office applications, run Word as administrator (right-click → Run as administrator) and try again.

Method 2: Through the command line (ospp.vbs)

Office uses the ospp.vbs tool (Office Software Protection Platform) to manage licenses.

1. Open CMD as administrator (right-click on Start → Terminal/Command Prompt (Administrator))
2. Go to the Office directory:

cd "C:\Program Files\Microsoft Office\Office16"

For 32-bit on 64-bit Windows: cd "C:\Program Files (x86)\Microsoft Office\Office16"

1. Install the key:

cscript ospp.vbs /inpkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX

1. Activate online:

cscript ospp.vbs /act

1. Check the status:

cscript ospp.vbs /dstatus

ospp.vbs command table

Method 3: Telephone activation

When online activation does not work — e.g. activation limit after hardware change:

1. In CMD as administrator, from the Office16 directory:

cscript ospp.vbs /dinstid

1. Save the displayed installation ID (Installation ID)
2. Call the Microsoft Poland number:
   • 00 800 121 1654 (free)
   • +48 801 802 000
   • +48 22 594 19 99
3. Provide the installation ID to the automated system or consultant
4. You will receive a confirmation code (Confirmation ID)
5. In CMD:

cscript ospp.vbs /actcid:CONFIRMATION-CODE

Hint: If the automated system suggests a website — press 0 or say nothing, the system will switch to the option of providing the ID.

If you need help, please contact us at [email protected] or call 00 800 121 1654.

Troubleshooting

Error 0xC004C008 — "Activation limit exceeded"

The key was used on another device.

1. Use phone activation (Method 3) — the consultant can unlock it
2. If it doesn't help — write to [email protected], we will exchange the key for free

"Unlicensed Product"

1. Check your internet connection
2. In CMD as administrator:

cscript ospp.vbs /act

1. If it doesn't work — reinstall the key:

cscript ospp.vbs /unpkey:XXXXX
cscript ospp.vbs /inpkey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
cscript ospp.vbs /act

"Product key is not valid"

• Make sure you enter the key from the order email (not from another source)
• Try entering it manually instead of copying (you'll avoid extra spaces)
• Check if you're not confusing zero (0) with the letter O, or one (1) with the letter I

"Activation required" after installation

This is a normal message. Follow the steps from Method 1 — the key will activate the product permanently.

Check activation status

Through the application

1. Open Word → File → Account
2. The Product Information section will show:
   • "Product activated" — everything is OK
   • "Activation required" — use one of the methods above

Through CMD

cscript ospp.vbs /dstatus

It will display: edition, license status, partial key, expiration date.

Frequently Asked Questions

Is activation one-time? Yes — after activation, the license is tied to the hardware. Re-activation is only needed after replacing components (e.g. motherboard).

Can I transfer the key to another computer? Yes. Uninstall on the old computer, install on the new one, and activate. If you've reached the limit — use phone activation.

How long is the license valid? The license is lifetime. Microsoft support for Office 2021 lasts until 13 October 2026 — after this date, Office will continue to work, but without updates.

Does activation require internet? Methods 1 and 2 require internet. Method 3 (phone) works without internet.

Need help?

• Email: [email protected] — we respond within a few hours
• Help center: pomoc.kluczesoft.pl
• Microsoft Poland phone: 00 800 121 1654 (free)