Sometimes you have different source code files from the version that built your code. Ideally you want the sources to be the same, so you know exactly what is going on with your code. but it happens that you know the particular method hasn’t changed or you know exactly what the diff is.
Or maybe you want to prevent this from happening, because you are not cool with it.
Go to Tools – Options – Debugging – General, and uncheck the “Require source files to exactly match the original version.”
When this option is unchecked, you can use source code files that don’t match the original, as shown below with the current statement highlight not fully extending the line.
and when it is checked, you get this error message. Pressing the default “No” button will bring up a File browse dialog to locate your source files.