Datum Transformation Issue for Nord Maroc Lambert Conformal Conic (EPSG: 26191) in ArcGIS Pro 3.2

BENSEDDIK — Tue, 10 Dec 2024 14:06:40 GMT

Hello,

I am using ArcGIS Pro 3.2 and am encountering a problem with datum transformations for an enterprise geodatabase feature layer in the Nord Maroc (EPSG: 26191) coordinate system. The issue is detailed below:

The layer’s projected coordinate system is Nord Maroc Lambert Zone 1 (EPSG: 26191).
The geographic coordinate system (GCS) should be Merchich (WKID: 4261), but it isdefined incorrectly with a WKID of 0.
I attempted to fix this by:
- Using the Define Projection tool to correctly set the GCS to Merchich (WKID: 4261).
- Using the Project Tool to reproject the data to Nord Maroc Lambert Zone 1 (EPSG: 26191), applying a datum transformation from Merchich to WGS84.

After applying these fixes in ArcGIS Pro 3.2, the data appears displaced. Instead of being located in Morocco, the polygons are shown in Spain. I suspect the issue is related to the missing or incorrect datum transformation during the reprojection process.

I also have a previous installation of ArcGIS Pro 2.8 on another PC. When I open the same layer in ArcGIS Pro 2.8, it displays correctly:

The layer’s spatial reference is defined correctly without requiring redefinition.
The layer’s geographic position is correct, and the polygons align properly with Morocco.

This suggests the problem is specific to my current ArcGIS Pro 3.2 installation or its handling of the layer’s datum transformation.

This is how the coordinate system is defined in arcGIS Pro 3.2 :

and this is the same layer coordinate system in arcGIS Pro 2.8 :

Could the problem be caused by missing ArcGIS Coordinate Systems Data, and will installing this resolve the issue in ArcGIS Pro 3.2?
What steps can I take to ensure the data is properly projected and aligned in ArcGIS Pro 3.2?

Any insights or suggestions would be greatly appreciated!

Thank you in advance!!

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Datum Transformation Issue for Nord Maroc Lambert Conformal Conic (EPSG: 26191) in ArcGIS Pro 3.2