If the build process fails, this may be due to a too old or too new Java version. See Where to get Java for more info on getting the latest version.

Alternatively, when using the Ant build and if the error message says something about a class – or class definition – not being found, you may not have all the build libraries installed. Consult firebird-documentation/lib/_readme_libs.txt and follow the instructions.

If a PDF build ends with BUILD SUCCESSFUL but a couple of lines above it says “No files processed. No files were selected...” and indeed the PDF file isn't there, this may be caused by spaces and/or other “naughty” characters in the file path. See the warning in Building the HTML and PDF docs.

If a PDF build succeeds but you find ugly things within the produced document, have a look at the next section: Improving the PDF. You may find the solution there.

If anything else goes wrong and you can't get it right, ask for help on the firebird-docs mailing list. Please give a good description of your problem so we can help you better. If you aren't on the firebird-docs mailing list yet, visit https://lists.sourceforge.net/lists/listinfo/firebird-docs for information and subscription.