As I advised the other poster:
There are a lot of problems with Windows 8.1 and the Microsoft Store.
This is how one poster here solved their problems with the Store>
I contacted Microsoft support, got the virtual agent and asked her to chat with live person. Told the person my problem and it was fixed in an hour.
To contact Microsoft Support:
What can we help you with?
https://support.microsoft.com/en-us
Contact support
http://windows.microsoft.com/en-us/windows/contact-support
Also: https://partner.support.services.microsoft.com/en-au/contact/menu/software/windows/setup/