Also, don't understand this bit :
data source info in the rectangle properties and this is what it says:
Data Type: CAD Polygon Feature Class
Location: D:\GIS_databas
Feature Dataset: cadtest3 utan kurvor med ruta.DWG
Feature Class: Converted_Graphics
Feature Type: Simple
Geometry Type: Polygon
Coordinates have Z values: Yes
Coordinates have measures: No
Projection File:
D:\GIS_databas\ESRI_CAD.prj
Projected Coordinate System: SWEREF99_12_00
Projection: Transverse_Mercator
False_Easting: 150000,00000000 etc
What application is giving you this. Why the reference to a projection file?
If I look at a georeferenced CAD in ArcCatalog it doesn't show me a reference to another prj file,
it simply shows me the coordinate system. ie the prj is the same name as the CAD.