Meyszner began his career as an officer in the Gendarmerie, served on the Italian Front during World War I and reached the rank of Major der Polizei by 1921.
Meyszner memulai kariernya sebagai seorang perwira di Gendarmerie, bertugas di Front Italia saat Perang Dunia I, dan meraih pangkat Major der Polizei pada 1921.