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Technical Article   FAQ:  Where is the Coordinate Systems folder, and where are the projection files at ArcGIS for Desktop 10.1 and later?

Article ID: 39488
Software:  ArcGIS for Desktop Advanced 10.1, 10.2, 10.2.1, 10.2.2, 10.3 ArcGIS for Desktop Standard 10.1, 10.2, 10.2.1, 10.2.2, 10.3 ArcGIS for Desktop Basic 10.1, 10.2, 10.2.1, 10.2.2, 10.3
Platforms: N/A


Where is the Coordinate Systems folder, and where are the projection files at ArcGIS for Desktop 10.1 and later?


ArcGIS for Desktop now supports over 5,000 geographic, projected and vertical coordinate systems. Before ArcGIS 10.1, coordinate systems were included in the installation directory as .prj files in a Coordinate Systems folder. Installing the .prj files required a significant portion of the time taken up by the software installation process.

Each projection file is only a few hundred bytes when opened in a text editor, but because the information in the PRJ file must be stored in a block, with specific configuration, storage for one file requires four kilobytes for storage. Multiplying that by about 5,100 files, and the text projection files require about 20 MB for storage or installation.

To improve the installation experience and simplify localization support, the files are no longer included in the installation package. Instead, a virtual directory structure is built directly from the coordinate system data.

Commonly used coordinate systems can be exported to a Favorites folder. The physical location of this folder is the Application Data\ESRI\Desktop10.1\ArcMap\Coordinate Systems folder in the Windows profile directory.

 This path changes with each version. For example, at version 10.2.x the folder location is:

C:\Users\<user>\AppData\Roaming\ESRI\Desktop10.2\ArcMap\Coordinate Systems

Custom .prj files can also be copied into this folder for use in ArcGIS. The Favorites directory can be accessed in ArcMap when setting the coordinate system of an ArcMap data frame on the View > Data Frame Properties menu, Coordinate System tab.

The coordinate systems in the Favorites directory are also available in ArcToolbox when using the Define Projection tool or the Project tool.

Related Information

Created: 10/28/2011
Last Modified: 9/23/2014

Article Rating: (7)
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By db_tulga - 11/09/2014 7:14 PM

The article needs to be updated.

I'm using ArcGIS 10.2.2 and I need Kavrayskiy projection. In the ArcGIS don't have this projection. Can anyone help me? Maybe I need PRJ file. Thanks BT


By abenefiel - 10/23/2014 9:29 AM

The article is incorrect or the solution didn’t work.

I see no "Coordinate Systems" folder under the path listed. There is only a "Templates" folder. I have all hidden folders in "show" setting. Any help?


By BTLeslie - 10/10/2014 2:15 AM

Other - See details below.

Very inconvenient to add many projections to my favourites - seems like they must be done one at a time, lots of scrolling up and down the little coord system window.....I'm so bored. Please think about usability. Please.


By dp3lw - 03/13/2014 12:32 PM

Other - See details below.

I'd have to agree with everyone else. Having a favourites area for a user is fine, but providing everyone with our corporate standard projection becomes an extra step that the user must go through. We use to update the Coordinates folder with a custom folder, of projections, as part of an install.


By stanford44 - 02/27/2014 2:46 AM

Great article! It helped a lot!


By hawkeye_rgbg - 11/22/2013 4:04 AM

Other - See details below.

It has become very inconvenient now handling the projections. It would be very good, if the user could (easiely) add a path with additional projections. For example somewhere on a network drive. We have six projections which are very important for us. Until now the users could simple copy a folder with these files.

By danielri - 02/27/2013 3:54 PM

The article is incorrect or the solution didn’t work.

This article does not address the key issue, it is now difficult to deploy a set of custom projection files agencywide so every user has your agencies prefered .prj files listed in the dialog. Putting them in a local user area is 'ok' but does not work well when you have over 1700 machines to update. At a minimum, .prj files located in c:\users\all users\ should be picked up and listed in the favorites.


By maphew - 01/17/2013 1:36 PM

I would like to see a new article that discusses the topic outlined below.

Ok, thanks for that. I understand how a dynamic calculated system improves performance and storage efficiency. Now my question becomes where is the data in "directly from the coordinate system data."?