QGIS does not have the coordinate reference system I need, So I decide to define a new custom Geographic coordinate system. To define a CRS, I selected customProjection Custom CRS from the Settings menu. The Custom Coordinate Reference System Definition dialog requires only two parameters to define a user CRS: 1) A descriptive name 2) The cartographic parameters in PROJ.4 format

So I did that as you can see from the picture: enter image description here

But when I click OK to add the projection within QGIS a pop up message with an error show up and with very different set of parameters in the parameter window. the error message says I have set up a proj string definition equivalent to esri:102218 which is not really the same. I don't really know if this a bug or something went wrong with my parameter setting.

enter image description here

2 Answers 2


Select the WKT Format (not the Proj String as shown in the question screenshot)

https://epsg.io/4919 copy text function

enter image description here

Then Validate


The problem is not with your new CRS, but with an old CRS defined before the upgrade to 3.12 version.

That CRS is a Generated CRS. In older versions, when you load a layer with an unknown CRS, a custom CRS was created.

Now, the ESRI authority was added to the PROJ database, custom CRSes are not automatically generated, and custom definitions that are equal to a known CRS are not allowed.

Just remove that old automatically generated CRS, you will not need it any more.

  • I have a similar issue trying to create a Mercator projection with a new pole and 40deg rotation. If I use the PROJ option in Qgis 3.16.11 it says the CRS matches the world Merc EPSG. Any ideas how to fix?
    – Seagus
    May 4, 2022 at 21:02
  • Hi, feel free to create a new question for that topic. May 4, 2022 at 22:33

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