Windows Store in-app purchase error - your purchase couldn't be completed
Can't complete an in-app purchase in Windows Store on a Windows 8.1 tablet. The in-app purchase was for Island Tribe game (to upgrade it to the full version).
After clicking buy and entering the password, following error would show up:
Your purchase couldn't be completed
Please try again later.
Trying again later didn't really help... The whole thing was making a certain 6 year old quite upset, so a swift resolution was required!