Conversion of vssx files to vss file format

The only way to convert vssx to vss, aka Visio stencils to shapes, would be to open the .vssx files in Microsoft Visio 2013, right click on the stencil header, select Save As, and pick the .vss as the desired file type. This will save it to a VSS format (smart shapes data).

Open VSSX file    Open VSS file

Related software

Microsoft Visio icon

Microsoft Visio

A vector based diagramming software from Microsoft