Once you have completed your tax return on taxx.lu, you can print it out and send it to your tax office by post.   As a first step, it is very important that you open your tax return with Adobe Acrobat Reader. On Mac:  Click the printer icon (or CTRL-P). Click on "Advanced".  Tick the "Print As Image" check box.   Click "OK" at the bottom right.   On Windows:  Press the printer icon (or CTRL-P).     After printing, do not forget to sign the last page and send your attachments.