Defining the projection for raster images as NAD 1983 StatePlane Montana FIPS 2500.prj does not 'stick'

Description

Defining the projection for raster images georeferenced to NAD 1983 StatePlane Montana FIPS 2500.prj, with units of meters, does not work. The spatial reference of the image continues to show as 'undefined'.

Cause

FIPS code 2500, with units of meters, has not been added to the raster code base.

Solution or Workaround

1. In ArcCatalog, navigate to Tools > Options > General tab. In the upper window, check the box 'Coordinate Systems' to display the Coordinate Systems folder in the TOC.
2. Right-click on the Coordinate Systems directory, and click on File > New Folder. A new folder is created in the Coordinate Systems directory, along with the Geographic Coordinate Systems and Projected Coordinate Systems folders.
   
   Rename the New Folder 'Custom PRJ Files', without quotes.
3. Open Coordinate Systems > Projected Coordinate Systems > State Plane > NAD 1983. Select 'NAD 1983 StatePlane Montana FIPS 2500.prj'; right-click and copy it.
4. Navigate to Coordinate Systems > Custom PRJ Files, and paste. The projection file is then pasted into the folder.
5. Right-click on the copy of the projection file > Rename, and change the name of the projection file, but retaining the '.prj' extension.
   
   A suitable name might be:
   
   Montana SP nad83 meters.prj
   
   

   Note:
   Spaces are allowed in the name in this location.

   
   
6. Double-click on the renamed projection file to open the properties. In the NAME box at the top of the dialog box, enter a new name for the projection file. A suitable name might be:
   
   'Montana_SP_nad83_meters'
   
   

   Note:
   Spaces are NOT allowed in the name in this location. Underscores may be used.
   
   Do NOT enter the .prj extension.

   
   
7. The renamed projection file can be used to define the projection for raster images, georeferenced to NAD 1983 StatePlane Montana FIPS 2500 meters and the correct projection definition can now 'stick'.