Error

"The loaded .prj file does not contain the TOWGS84 parameter. This may lead to incorrect georeferencement."

Error when importing .prj file with the coordinate system.

Description

When importing the coordinate system from a .prj file in Images Properties Editor or GCP/MTP Manager or Output Coordinate System you may receive:

"The loaded .prj file does not contain the TOWGS84 parameter. This may lead to incorrect georeferencement." 

Cause

The message pops up if the coordinate system is not in our database; this is a warning message and not necessarily an error. It means the software could not read properly the syntax from the imported file as the TOWGS84 parameter is missing. If the content of the file is correct, by clicking OK the coordinate system is imported in the project.

The TOWGS84 parameter defines the transformation parameters (3 translations, 3 rotations, scale) between the datum of the .prj defined coordinate system and the WGS84 system. When this parameter is not in the .prj file the software cannot perform the transformation between the WGS 84 system of the images to the coordinate system defined by the .prj. 

Solution

1. Click OK. If the software can recognize the coordinate system, it will appear in the next pop up window Edit coordinate system.
2. Verify that the right new coordinate system appears in the pop up window Edit coordinate system.
3. In the main window, verify that the points representing the images are located correctly in the place where they are suppose to be located.