There are two way to check.first is you can directly check whether key contain A or not in binding like this:-. but i think this is not the better way so instead of this you can use ko.computed to check.
Check for operating system information in Windows 7. 1  Click the Start button , enter Computer in the search box, right-click Computer, and then click Properties. 2  Look under Windows edition for the version and edition of Windows that your PC is running.
Once you put in that product key, you can then download the appropriate version and install with that same key. If you registered your copy of Office 2013, you don't even need the product key. Just visit office.microsoft.com, click Install Office, and then log in to your account to download it.f you registered your copy of Office 2013, you don't even need the product key. Just visit office.microsoft.com, click Install Office, and then log in to your account to download it.