Office LTSC Standard 2021 genuine product certification problem when reinstalling PC

Question

I have purchased and used 20 Office LTSC Standard 2021. When I reinstall the office program from the old PC to the new PC, I want to delete the office program from the old PC, install it from the new PC, and authenticate it, so I get a message that all the activation keys have been used.

Answer 1

Hi @상희 하

Office Long Term Service Channel (LTSC) 2021 is one of volume license versions of Office. It generally uses KMS, MAK to activate Office. So how did you activate Office?

Besides, could you please tell us how did you re-install Office?

I get a message that all the activation keys have been used.

If you use KMS activation, the KMS clients need to be greater than 5 and need to install GVLK, then they can connect to the KMS host to apply for activation.

• If it is a MAK activation method, the MAK key can be reused and activated online as long as it is within the number of license agreement that you purchased.
• The reference: Activate volume licensed versions of Office by using KMS and Activate volume licensed versions of Office by using MAK

If your Office is not LTSC versions, and is retail version of Office 2021. You can download and install Office from www.office.com, or use your Microsoft account to sign in to account.microsoft.com.

• If you are prompted that phone activation is required, please check the Microsoft phone support number in your country or region in this document and contact to Microsoft for further activation support.
• The reference: Download, install, or reinstall Microsoft 365, Office 2024, or Office 2021 on a PC or Mac.

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