Is Activating Windows necessary for an ASR Appliance?

Question

Is Activating Windows necessary for an ASR Appliance?

Joseline Monica 0

Hi All,

We are setting up a Disaster Recovery system using Azure Site Recovery to protect our On-Prem VMware servers. We have created an Appliance server by deploying a OVA template downloaded from Microsoft Azure. This is not joined to the Domain. We have deployed and configured ASR Appliance without any issues. However noticing a " Activate Windows" message. It is unable to do this because its not able to detect the KMS server automatically.

For an ASR Appliance is it mandatory for Windows to be Activated or can we proceed without Activating.

If it is mandatory can we manually activate by providing the KMS server FQDN?

Kindly help.

Regards,

Joseline

Lakshma Reddy Vattijonnala 1,005 Reputation points Microsoft External Staff Moderator

2026-06-22T08:35:33.3+00:00

Hi @Joseline Monica I hope you had a chance to review the information shared earlier, and I hope this information has been helpful! If you still have questions, please let us know what is needed in the comments so we can help you to assist further

2 answers

Your answer

Lakshma Reddy Vattijonnala 1,005 Reputation points Microsoft External Staff Moderator

2026-06-22T08:35:33.3+00:00

Hi @Joseline Monica I hope you had a chance to review the information shared earlier, and I hope this information has been helpful! If you still have questions, please let us know what is needed in the comments so we can help you to assist further

Answer 1

Hi @Joseline Monica Thank you for the clear description of the issue.

The Azure Site Recovery (ASR) replication appliance is deployed with a Windows evaluation license that is valid for 180 days. Microsoft documents that the license included with the OVF/OVA deployment is an evaluation license and that, for uninterrupted usage, Windows should be activated with a valid procured license before the evaluation period expires.

The"Activate Windows" notification on the appliance is therefore expected when the operating system has not yet been activated.

Microsoft further notes that if the evaluation license expires without activation, this can result in frequent shutdowns of the appliance, which may impact or interrupt Site Recovery replication activities. For that reason, Microsoft recommends activating the appliance before the evaluation period ends, especially for ongoing production disaster recovery deployments.

If your organization uses Key Management Services (KMS), Microsoft supports updating the license by using either:

A standalone product key, or
A KMS-based activation method.

Since Windows activation is an operating system licensing function rather than an Azure Site Recovery function, any activation failures would typically need to be investigated from a Windows licensing perspective.

Please find the below references for more information:

So, the appliance can continue to function during the evaluation period. However, for long-term or production use, activating Windows before the 180-day evaluation expires is recommended to avoid potential shutdowns that could affect replication operations.

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Answer 2

Marcin Policht 94,940 MVP Volunteer Moderator

Nope - unless you intend to use it long-term. If that's your intention, you can manually configure your KMS server using its FQDN to complete the activation process. The Microsoft OVA template ships with a Windows evaluation license that lasts for 180 days.

If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.

hth

Marcin

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