Good Day, Environment: Windows Server 2008R2 and Windows 7 I have question regarding the KMS host. 1) There is a Volume Activation Expiration, is about 180 days, what will happen after end of this 180 days? Will it lock down the PC, or it still can be use? Can we set it longer or maybe set to unlimited? 2) If the KMS host down, we cannot retrieve any of the activation data, setup a new KMS host, will all the client search for the new KMS host? Or I need to redo the activation for all the client? Thank you

Hi Nakamori, To answer your first question, client activations are valid for 180 days. This period is called the activation validity interval. To remain activated, KMS clients must renew their activation by connecting to the KMS host at least once every 180 days. By default, KMS client computers attempt to renew their activation every seven days. After a client’s activation is renewed, the activation validity interval begins again. This is by design, you cannot modify it. If client doesnot reactivate after 180 days, it will return to the evaluation period. To answer your second question, you can setup a new KMS host if the current KMS host is down. Each KMS key can be installed on up to six KMS hosts, which can be physical computers or virtual machines. After activating a KMS host, the same host can be reactivated up to nine more times with the same key. If Dynamic DNS is enabled in your network environment, the KMS host SRV record will be created automatically in DNS, and by default the KMS client automatically attempt to discover KMS host. Since the original KMS host name is cached in KMS client. Disabling the auto-discovery of the KMS client can clear the cache. If auto-discovery is disabled, you can re-enable it by running slmgr.vbs /ckms at a command prompt. Otherwise, you can also manually assign a KMS host to the client by running slmgr.vbs /skms <value>:<port> where value is either the KMS_FQDN, IPv4Address, or NetbiosName of the KMS host and port is the TCP port on the KMS host. For more information, please refer to the link below. http://technet.microsoft.com/en-us/library/dd979804.aspx Regards, Karen Ji Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. ” This posting is provided "AS IS" with no warranties, and confers no rights. On July 1st we will be making this forum read only. After receiving a lot of feedback from the community, it was decided that this forum is a duplication and therefore redundant of the General Forum. So, until July 1st, we will start asking customers to redirect their questions to the General Forum. On June 11th, CSS engineers will move any new threads to the General Forum. Please post a reply to the announcement thread if you have any feedback on this decision or the process. You can also email WSSDComm@microsoft.com.

Dear Karen, Thank you very much for the information you provided. But I still not really understand on the 2nd answer. For example, if KMS host 1 is down, then we immediate setup KMS host 2, means I need to clear the KMS cached at all the client PC? What will happen if I have more than 1000 PCs? Do I need to clear the cached for all the client, so it will auto discover the KMS host 2? Thank you.

Hi Nakamori, The KMS client will attempt to communicate the original KMS host server if the cach isn't cleared. If it fails, they will query DNS for KMS host SRV record and find the new KMS host as long as auto-discovery is enabled. So you don't have to manually change anything in KMS clients. Clearing the cach on the client computers will make them detect the new KMS host faster. Regards, Karen JiPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. This posting is provided "AS IS" with no warranties, and confers no rights.

Dear Karen, Thank you for the reply. Means that, if KMS host 1 is down, and we immediate setup KMS host 2, the client actually will query from DNS to look for the new KMS host? It will took how long for client to query for the new KMS host? By activating the auto-discovery, is it using the command slmgr -ckms? And what is the command for clear the DNS cache on client machine? Thank you.

Hi Nakamori, By default, KMS host will be cached in KMS client computer, if the system can no longer contact the working KMS host, discovery will be attempted again. It is just like the KMS client searches for the KMS host for the first time. It will not take long. If the activation fails, KMS client will try to contact KMS host again at an interval of 120 minutes. If you would like to disable the auto discovery, you can manually assign a KMS host for the client by running the command slmgr.vbs /skms <value>:<port>. You can also disable KMS host caching by running the command slmgr.vbs /ckhc on KMS client. This setting instructs the client to use DNS auto-discovery each time it attempts KMS activation. For more information, please refer to the TechNet article below. Volume Activation Technical Reference Guide http://technet.microsoft.com/en-us/library/ee355153.aspx#EXAA Regards, Karen JiPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. This posting is provided "AS IS" with no warranties, and confers no rights.

Can you disable KMS host caching for Office 2010 clients as well? I have tried slmgr /ckhc which works fine for the Windows OS but my office installations still cache the last host that was used. perhaps there is some ospp.vbs command that I haven’t found yet? thanks Adam