How to install Microsoft Office 2021 Standard — complete instructions

Before You Start

What Does Office 2021 Standard Include?

Office 2021 Standard (LTSC) is a one-time purchase of an office suite with 6 applications:

What's NOT Included in Standard?

• Access (databases) — available only in Professional Plus edition
• Teams — pre-installed only in Professional Plus. Can be downloaded separately.

Standard vs Professional Plus

System Requirements

Support

• End of Support: October 13, 2026
• License: Lifetime (one-time purchase, no subscription)
• After 2026, Office will continue to work, but without security updates

Step 1: Uninstall the Previous Version of Office

If you have Office 2016, 2019, or Microsoft 365 installed — uninstall it before installing.

1. Settings (Win + I) → Apps → Installed Apps
2. Search for "Microsoft Office" → ⋯ → Uninstall
3. Restart your computer

If the standard method doesn't work — download the SaRA tool from aka.ms/SaRA-officeUninstall.

Your Word, Excel, etc. documents will not be deleted — the uninstallation only affects the program.

Step 2: Download and Mount the ISO File

1. Open the email with the order confirmation from KluczeSoft
2. Click the link to download the ISO file (approx. 3–4 GB)
3. After downloading: right-click on the .iso file → Mount
4. Windows will open the file as a virtual DVD drive (e.g., D: or E:)

Don't see the "Mount" option? Right-click → Open with → Windows Explorer.

Step 3: Run the Installation

1. Open the virtual drive in File Explorer
2. Double-click Setup.cmd (or Setup.exe)
3. When prompted by UAC, click Yes

SmartScreen blocks it?

1. Click More info → Run anyway

The installation takes 5–15 minutes. Do not close the window or shut down your computer.

For assistance, please contact us at [email protected] or call 00 800 121 1654.

Step 4: Activate Office with the Product Key

Method 1: Through the Application (Recommended)

1. Launch Microsoft Word
2. File → Account → Change Product Key
3. Enter the 25-character key from KluczeSoft
4. Click Activate
5. The status will change to: "Product activated"

Method 2: Through CMD (ospp.vbs)

1. Open CMD as an administrator
2. cd "C:\Program Files\Microsoft Office\Office16"
3. Install the key:

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

1. Activate:

cscript ospp.vbs /act

1. Check the status:

cscript ospp.vbs /dstatus

Method 3: Telephone Activation

When online activation does not work (e.g., activation limit):

1. cscript ospp.vbs /dinstid — save the installation ID
2. Call:
   • 00 800 121 1654 (free)
   • +48 801 802 000
   • +48 22 594 19 99
3. Provide the installation ID → receive a confirmation code
4. cscript ospp.vbs /actcid:CONFIRMATION-CODE

Useful Commands

Step 5: After Installation

Dismount ISO

Explorer → This PC → right-click on the DVD drive → Eject

Updates

Word → File → Account → Update Options → Update Now

Outlook

Launch Outlook → enter your email address → the wizard will configure the account automatically (Gmail, Outlook.com). For company servers, manual IMAP/SMTP configuration may be required.

Troubleshooting

"Activation limit exceeded" (0xC004C008)

1. Use telephone activation (Method 3)
2. Or write to [email protected] — we will exchange the key

"Unlicensed product"

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

cscript ospp.vbs /act

1. If it doesn't work:

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

Installation doesn't start

1. Restart your computer
2. Temporarily disable antivirus software
3. Run Setup.cmd as administrator (right-click → Run as administrator)

Download link doesn't work

Write to [email protected] — we will send a new link within a few hours.

Frequently Asked Questions

Does Office 2021 Standard require a subscription? No. One-time purchase, lifetime license, no monthly fees.

Does Standard include Publisher? Yes — Office 2021 Standard includes Publisher. In the newer Office 2024, Publisher has been removed, so if you need Publisher — Office 2021 is a better choice.

How long will I receive updates? Until October 13, 2026. After this date, Office will continue to work, but without new updates.

Can I transfer it to a new computer? Yes. Uninstall on the old one, install on the new one, activate with the same key. In case of a limit — use telephone activation.

Is Office 2021 compatible with Windows 11? Yes, fully compatible with Windows 10 and 11.

Do I need Professional Plus instead of Standard? Only if you need Microsoft Access (databases) or pre-installed Teams. For most users, Standard is sufficient.

Need Help?

• E-mail: [email protected]
• Help Center: pomoc.kluczesoft.pl
• Provide your order number and error message