This article explains how you can rearm Office 2010 and for what you need this feature.

Office 2010 is certainly the best Office suite out there. However, compared to Office 2007 it has one major drawback: Like Vista and Windows 7, Office 2010 has to be activated. However, Office 2010 behaves a little different than Windows if it is not activated. Rearming Office 2010, that is resetting the grace period, works similar as rearming Windows.

Office 2010 Reduced Functionality Mode

Retail versions of Office 2010 will only run in Reduced Functionality Mode (RFM) after the grace period of 30 days has been exceeded. In RFM Office, documents can only be viewed but not modified.

Volume editions of Office 2010 don’t have an RFM. However, Office will start nagging users with messages after 25 days. You can just imagine how many helpdesk calls it will provoke if you don’t ensure that Office 2010 has been activated during this grace period.

Activating Office 2010

You can use the latest version of the Key Management Host (KMS) or activate Office 2010 with VAMT. Either way shouldn’t be doable within 25 days after the installation.

However, it might be difficult to activate Office 2010 during the grace period if you deploy a pre-installed Office with an OS image. The grace period begins immediately after you installed Office 2010 on your master PC. If you have to perform other configurations before you create the master image, then it is quite possible that 25 days is too short. You also have to take into account that it might take some time until Office finds a KMS host or until you activate it manually.

This is where Office 2010 rearm comes in. This features allows you reset the grace timer to 30 days grace. If you rearm Office right before you create the OS master image, you can be sure that you have the full 25 days before users will bothered with Office activation notifications or before the retail edition goes into Reduced Functionality Mode after 30 days.

How to rearm Office 2010

You will find some complicated instructions on the Web of how to rearm Office 2010. Most of these articles were written before Office 2010 was released. There are also third party tools that allow you to rearm Office 2010. However, I recommend following Microsoft’s instructions. This topic is too sensitive to rely on third party tools.

To rearm Office 2010, you only have to run ospprearm.exe in %installdir%\%Program Files%\Common Files\Microsoft Shared\OfficeSoftwareProtectionPlatform from an elevated command prompt. "%Program Files%" has to be replaced with %Program Files (x86)% if you installed Office 2010 32-bit on Windows 64-bit.

Rearm Office 2010 - ospprearm.exe

Rearm Office 2010 – ospprearm.exe

Since you can rearm up to 5 times, you can run Office 2010 for 180 days (30 days + 5 x 30 days) without activating it, if you rearm it every time after the 30 days grace period has been reached.

Another effect of rearming Office 2010 is that the client machine ID (CMID) is reset. The KMS host uses the CMID to identify unique clients. This allows the KMS host to count Office 2010 correctly.

Rearming Office 2010 Trial

Office 2010 rearm could also be useful if you installed Office 2010 Trial. The Office 2010 Professional Plus Trial comes with a special activation code that will allow you to test Office 2010 for 60 days. There are reports on the web indicating that you can also rearm the trial version of Office 2010. Office 2010 Trial indeed comes with ospprearm.exe. However I doubt that rearming will work after you used the trial activation code because rearming makes only sense with an Office installation that hasn’t been activated.

Office 2010 Activation Wizard

Office 2010 Activation Wizard

You can run Office 2010 Trial without activating it but every time you launch the Office 2010 Activation Wizard will pop up. If you cancel this dialog, you can continue using the Office application. I suppose this will only work for 30 days. If you have experience with rearming Office 2010 Trial, please let me know.