I'm trying to buy (i.e. give Microsoft and some publisher my money) an app but when  try to set the billing address for my credit card it won't let me select my country, Mexico. My Windows 8.1 is installed in en-US, but surely (after 30+ of OS-making) Windows is smart enough not to assume that just because I'm using English, I'm from the U.S. So, what am I missing, how can I make the App Store accept my credit card? Or they're not accepting my pesos for the time being? I can buy Windows Phone apps well enough though. :(

Thanks in ad

Hi,

I suggest we change the region of your system to Mexico  to check the results:

How to Change the Region Home Location of your PC in Windows 8 and 8.1

http://www.eightforums.com/tutorials/14344-location-change-region-home-location-windows-8-a.html

keep post.

My regional settings are set to Mexico (i.e. location, time zone, etc.). The only thing amiss is that I use English (United States) as my language, and the Store assumes that I'm from the US. 

Thanks in advance.