Office 2021 LTSC Activation

I have Installation ID for office 2021 LTSC and can't get confirmation id, and activation by call is not available

Office LTSC must be deployed rather than just installed and activated. See https://learn.microsoft.com/en-us/office/ltsc/2021/deploy .

If you need assistance, the local admin in your organization will have to get in touch with Microsoft business support. For more, go to https://learn.microsoft.com/en-us/microsoft-365/admin/get-help-support?view=o365-worldwide .

Hello @Mahmoud Abdulghany,

I understand that you already have the Installation ID for Office LTSC 2021, but you are unable to obtain the Confirmation ID because telephone activation is not available.

To obtain a Confirmation ID for Office 2021, you will need to complete the telephone activation process:

These steps are intended as general guidance. Because system configurations and environments can differ, the behavior and results may vary between devices. Further troubleshooting may be required based on the specific setup of the affected systems.

1. Open an Office application, such as Word, and go to File > Account.
2. Under Product Information, select the activation option if it is displayed.
3. If prompted to choose an activation method, select telephone activation.
4. Choose your country or region to receive the correct activation phone number.
5. Call the number provided and provide the Installation ID shown in the wizard.
6. After the Installation ID has been validated, you will receive a Confirmation ID.
7. Enter the Confirmation ID into the Activation Wizard to complete activation.

If telephone activation is unavailable or unsuccessful, please verify that you are using a valid Office 2021 product key and that the edition installed matches the license you own (for example, Office Professional Plus 2021, Standard 2021, etc.).

If the product key was purchased from a third-party seller or reseller and the issue persists, you may also contact the seller or licensing provider to verify the validity and activation status of the license.

Please note: Office LTSC 2021 is approaching the end of support in October 2026. After the end-of-support date, it will no longer receive security updates, bug fixes, or technical support. If applicable, you may also consider upgrading to a currently supported version of Office like Microsoft 365.

Kind regards,