ST4 schema no longer functions with Studio 2019

Question

I have recently upgraded to Studio 2019 on my laptop. 
 The XML (ST4 schema) files are no longer converted correctly, although this worked once! 
 I have tried importing several XML (ST4 schema) files that were converted correctly with Studio 2017 - they are always converted as XML: Any v 1.2.0 even though I have deactivated the associated checkbox! Does anyone have an explanation for this behavior? 
 PS I have reimported the ST4 settings and double-checked that they are activated.

Anthony Rudd · Answer

Jerzy Czopki brought me on the path to solving the problem; the associated template settings had the wrong file settings assigned, unfortunately the current file settings cannot be browsed.

Trados Studio > 1. Trados Studio

ST4 schema no longer functions with Studio 2019