I came across this error recently when opening a solution and building for the first time. It appears the project was not being built with the solutions and, thus, the executable was missing. Fortunately, the fix is simple.
To fix this, right click the solution in the Solution Explorer. Select "Properties." Click "Configuration Properties" from the menu on the left. Select "Configuration" from the drop-down if necessary. Find the project of interest in the list of project contexts to the right. Mark the checkbox in the "Build" column for that project.