Define Projection crack-down

[AustinStreetman]

With ArcPro 3.5, ESRI has cracked down on letting us define the projection on a feature class that has a projection. We have been importing an existing schema from an XML and then using Define Projection in a model to redefine the projection for the new project. In 3.5, this no longer works. We tried it in arcPy as well. 

This seems like an unfortunate level of hand-holding. ESRI should trust users to know when it is appropriate to redefine a projection. 

[MollyJackson]

I didn't see this thread when I started my own thread on the topic. My thread I am running into the same issue with the upgrade to 3.5. At first I thought it was because I was trying to use Define Projection on an undefined dataset. With further testing today, I am unable to use Define Projection on any dataset or feature class with a previously defined coordinate system either. If you read my thread, you'll see ESRI's response when I submitted a case. They told me I'm out of luck--it's a known error, and they don't plan on changing it.

I also just got off a chat with a support analyst, and here is the response I was given: "Geodatabase feature datasets and feature classes are not designed to have their coordinate systems changed after creation. The ability to update the coordinate system on feature dataset was an oversight and should not have been allowed. At ArcGIS Pro 3.5, that loophole was blocked. The change was on purpose. The new workflow is to make sure that a feature dataset or feature class has the correct coordinate system upon creation."

The ArcGIS Pro documentation states that the Define Projection tool: "Overwrites the coordinate system information (map projection and datum) stored with a dataset. This tool is intended for datasets that have an unknown or incorrect coordinate system defined."

But it apparently doesn't anymore. There are a number of caveats in the documentation.

[Nick_Creedon]

Thank you for this update. This is good to know. The "Project" tool is probably the better way to go, especially when the data is already projected one way. It will add the proper transformations to the data, but it does create a new layer that you now have to work with.

Project Tool:  https://pro.arcgis.com/en/pro-app/latest/tool-reference/data-management/project.htm 

[ChristalHigdon_USFS]

It is not the better way to go in 3.5, as it loses a bunch of our data structure in the parcel fabric dataset:
Before Project:

After Project:

Even some of the out-of-the-box relationships Esri creates automatically in the Parcel Fabric get lost using the Project Tool. Really kills our workflow and productivity to make this change to the Define Projection tool, with no mention in the release notes, and no working alternative for our use.

[DavidPike]

Seems like the opposite of an enhancement.  Cui Bono?

[javalos]

I'm having the same issue! Hate that I have to uninstall and go back to 3.4 just to use an out-of-the-box Solution ESRI created themselves for user ease.

[DarylHochhalter]

Project is something you are trying to avoid if you are using the define tool!

[MollyJackson]

After two cases with support services regarding this issue, I've basically been told there's nothing they can do, and I should submit my request to ArcGIS Ideas. So here it is. The more kudos an idea gets, the more visible it is to developers:

https://community.esri.com/t5/arcgis-pro-ideas/allow-define-projection-to-work-like-it-used-to/idi-p...