Sage 50 Canada

I´m working with sage 50 CA 2016 SDK, and i have a problem with database connection. When I run this code in a console application successfully opens the connection, but when I run the same code in a Winform application , does not open the connection…

I am currently trying to reverse older invoices as opposed to writing them off to bad debt. I am able to pull up the old invoices, but upon clicking the "Reverse Invoice" button I receive a message that says "The transaction cannot be adjusted because…