Binding Source” the underlying provider failed on open

@Sergey I m trying trying and trying to learn creating applications. I have learned basics of most of the languages and tools. I have created very small applications like simple calculator etc, but now I have started creating application used in Markets or Store to create invoices, keep track of customer etc. whenever I post any question on any forum or ask someone how to get completed this project, they don't provide me the steps needed, instead pushes me to search out what to do first or just rates it down. Neither I have seen anyone creating application nor found any video tutorial which teaches complete Application creation. This is my problem which makes me mad to post like this one.