Q. What are three invalid characters at the beginning of my file?

The three characters at the top of your file is the "Byte Order Mark" of a UTF-8 file. By default, a Java file is created as UTF-8 with BOM. You can change the default code page for new files from Java Properties > File page > New Files button, and change the code page to Normal ANSI, or uncheck the Add a Unicode Signature (BOM) box.