While there are several reasons why you need to change the activation key, the main reason for this is that the particular key you are using was activated already in the past. Moreover, you get a green tick when it is valid. The last character became invisible, and you just have to wait until that digit showed up again. At the time, there was some kind of unwanted anticipation while the key was validated. This process of changing the software key is much better than the one that is used before, particularly the Microsoft Office 2007. It also activates the button so you can proceed with the task. If the key you enter is valid, the message window recedes from view. During this moment, the Continue button becomes inactive and gray. Moreover, there is a message that will ask you to wait while the key you entered is still validated. You only put the 25 alphanumeric characters, and it will be taken care of. When it comes to changing the product key in Microsoft Office 2010, there is no need to concern yourself with hyphens or CAPS. It will not activate, and it can cause problems along the way. When this happens, Microsoft will assume that you are trying to transfer the code to a new different computer. One uncommon but can likely happen scenario is that you have more than one Office software license and you put one product key on the wrong computer.
