Create backdoor / script to execute a key logger silently

Project Description: I have a working key logger for Windows, which once downloaded and executed on a users machine will install itself and silently log keys and record them in a log file. It will also set itself up to start with windows start up. But currently the application requires that the user lets the application run when downloaded, or explicitly execute the application at least once for it to install and keep logging. The application is a standalone EXE, written in C++, Visual Studio. I would like to have a solution in which the application can run and install into the user's computer as soon as it is downloaded completely silently WITHOUT windows asking any questions. You may use any technique necessary as long as it works! If you have ideas on how this can be achieved, please bid for the project with a detailed description of your strategy. Only bids with a sound strategy description will be taken into consideration.