diff --git a/EXE_Exchange.cpp b/EXE_Exchange.cpp
index 51389c0..8e59a40 100644
--- a/EXE_Exchange.cpp
+++ b/EXE_Exchange.cpp
@@ -71,6 +71,8 @@ ExeGetFileType( const string& sFilePath)
       return FT_STL ;
    else if ( sFileExt == "3MF")
       return FT_3MF ;
+   else if ( sFileExt == "3DM")
+      return FT_3DM ;
    else if ( sFileExt == "OBJ")
       return FT_OBJ ;
    else if ( sFileExt == "CNC"  ||  sFileExt == "XPI"  ||  sFileExt == "MPF"  ||  sFileExt == "ISO"  ||  sFileExt == "EIA")