In 1798, he became a civil servant in the Austrian Commissariat of War in Vienna where, from 1802, he took a career in catering there until his retirement in 1831.
For these reasons, Molitor is today regarded as one of the founding fathers of Austrian musicology.
[3] In Vienna, besides his civil servant job and particularly after his retirement, he made a name for himself as a performing guitarist, teacher and composer.
His works and published theories proved very influential on contemporary guitarists in Vienna such as Wenzel Matiegka and Ludwig Joseph Wolf.
In an extended foreword he explains not only the history of the guitar as an artistic solo performance instrument, but also presents a new way of notating polyphony and a modern compositional approach, which were eagerly taken up by his contemporaries and successors.