Automatic Coordinate System Conversions
When you retrieve a section from the Sketcher Palette or from a legacy file, it may include a coordinate system type that is unavailable in the current Sketcher environment. Under these circumstances, the coordinate system is automatically converted as follows:
• Horizontalvertical—Becomes a geometry coordinate system, in instances where geometry coordinate systems are available. In other instances, a construction coordinate system is substituted.

For Sketched Curve features, the geometry coordinate system generates a datum coordinate system outside Sketcher. Make sure to toggle the system to Construction if you do not want to create the datum.

• Construction or Datum—Becomes two perpendicular construction centerlines with a construction point at the intersection, in instances where horizontalvertical coordinate systems are available.
All other coordinate systems created before Pro/ENGINEER Wildfire 5.0, that are not needed for featurelevel information, are converted to construction coordinate systems.