All About Microsoft Office Product Keys

The Product Key in Microsoft Office is what helps you unlock your installation. You'll need it to activate your software otherwise after 25 uses it will go into "Reduced Functionality Mode" the same way the trial version does after expiration.  At that point the software is read-only and can't be used to create, edit or save documents.

Where Is My Product Key?

When you buy Microsoft Office you should be given a product key.  It's generally a 25-character code that looks like this:


NOTE: That is, obviously, *NOT* a valid product key code.

If you bought your software in a retail box you should find the key inside the shrink-wrapped package, usually on a card.

If you bought your software online for download then the product key should have been provided to you on your download confirmation page and will probably also be e-mailed to you.

If your software is an OEM version that came with your computer then you may find the product key on a sticker on the side of your system, or perhaps on a card that was included with the system documentation. (or both)  Keep in mind that the OEM version of the software can NOT be installed on any additional systems or moved to another machine. It's locked to the original machine; even when the original machine dies.

How Can I Tell If My Product Is Activated?

If it's not activated it will generally warn you on each startup with a dialog box offering to help you activate.  If you don't see that dialog but want to confirm go to the Help menu of the program.

In Office 2010 you get there by clicking File | Help.  On the right side of the screen you should either see a notice that the product is activated or you'll see a link that helps you activate the product.

Microsoft Office Activated

How Do I Enter My Product Key After Installation?

Go to Control Panel, Add/Remove Programs.  Find Microsoft Office 2010 and click "Change".  One of the options available should be "Enter Product Key".  Select that radio button and click Continue...the wizard will walk you through it.

Enter product key

How Many Machines Can I Install Office On?

Depends upon what version of Office you have (Home and Student or Professional Plus or...) and what type of license you have (OEM, Retail, Volume, Home Use...)

  • The Home and Student Edition can be installed on up to 3 machines.  Any three machines.  It is NOT approved for use in commercial ventures, though, so don't buy it to install on 3 machines at your company.  The Home and Student Edition does NOT include Microsoft Outlook, by the way.
  • The OEM and Product Key Card versions of Office are tied to a specific machine - the machine you got the software with. You can't move it to a new machine when that specific machine dies or install it on any additional machines.
  • The Retail and Volume License versions of the software can be installed on any machine, and moved to a new machine if you replace that machine later.  Additionally the retail version of the software can be installed on a desktop computer AND on a portable computer (i.e. laptop/netbook) as long as both machines are used by the same primary user.  So if you have a desktop at work and a laptop you use on trips you can install the same retail copy of Microsoft Office on both machines with no problems.

I Have Office 2010 Installed on Windows 7.  Can I Install the Same License in a Windows XP Mode Virtual Machine on the Same PC?

No.  The license specifically restricts you to one copy of Office per device.  You can install in the Windows XP Mode VM *INSTEAD* of the Windows 7 host OS, but not in addition to.

How Many Times Can I Reinstall Office On The Same Machine?

As many times as you want to.  If you reformat a machine that previously had Office installed, or you replace the hard drive on a machine that previously had Office installed, you can reinstall the same copy of Office on the same computer again without any penalty or problem.

If you try to activate it and it claims to have already reached the limit of activiations, just choose the Telephone Activation option, call the number provided, and explain to them that you're reinstalling on the same computer.  They'll take care of it.

I Just Bought Office 2010 to Upgrade my Office 2007. Can I Move Office 2007 to Another Machine?

That depends. If your Office 2007 came with the old computer, i.e. it's an OEM version, then the answer (as above) is no.  OEM licenses are locked to the machine they came on.

If you bought Office 2007 retail (i.e. you went to Best Buy or Office Depot or somewhere and got it in a box; or you bought and downloaded it from an online site) or if it's part of a Volume License then yes, you can move it.  Just uninstall Office 2007 from the old machine and install it on the new machine.

How Can I Get My Product Key If I Lose It?

If you have a working and activated copy of Office installed and you need to obtain your product key later (but can't find the original e-mail or card that indicated what it was) there are several 3rd party tools that claim to be able to expose it for you.  Here are a couple (Note: I haven't tested these):

If none of those work you can try calling the Microsoft Product Activation Center and ask for a new one. You'll want to have your original product CD-ROM available if possible and as much information about the originial installation as possible - such as purchase date, partial product key, etc.  The more information you have the more likely you are to get issued a new product key.

For more information on getting a new product key from Microsoft, read here....

What If I Have My Product Key But Can't Find My Office 2010 Disc?

Go to and download the trial version of the SAME TYPE (i.e. Professional or Home and Student or...), then activate it with your product key.

How Can I Be Sure My Software Is Genuine?

Some unscrupulous operators sell fake Microsoft software.  You may have even purchased a computer that has bogus Microsoft software on it.  Or maybe you're getting a warning from your software that it might not be genuine.  If you want to validate your software Microsoft has a free online tool to do it.

Go here: and on the left side you'll see a "Validate Now" box that offers to let you Validate Windows or Validate Office.

What If I Can't Activate?

If you try to activate and it tells you that your product key is invalid or that you've already activated the product too many times then you should go to this article and run the FixIt at the bottom of the page.

More Information:

product-key-of-microsoft-office-2010  office-2013-pro-plus-key  office-2013-key  office-professional-plus-2013-activation-key  Windows-Server-2008-Standard-Edition-key  buy-an-activation-key-for-windows-7-online  windows-server-2008r2-key  windows-7-ultimate-product-key  office-2010-7-august-2013-key  Office-Product-Keys