The most frequent reason people search for this file is because they encounter one of the following error messages when opening a DWG file:
You need to write a .shp (text-based shape definition) file first, then compile it using AutoCAD's COMPILE command.
Example of a .shp file (which compiles to .shx):
;; aeccLand.shp - Custom land use symbols
*0,4,AECCLAND
6,2,2,0
*1,6,ARROW
001,2,010,014,002,0
*2,14,TREE
003,5,001,001,001,001,001,001,001,001,001,001,001,0
You then compile this with:
COMPILE aeccLand.shp
Which generates aeccLand.shx
You are opening a drawing created in AutoCAD Land Desktop 2004, 2005, or 2007 using a newer version of vanilla AutoCAD (e.g., AutoCAD 2023 or 2024). Modern AutoCAD installations do not automatically include legacy Land Desktop components.
AutoCAD will automatically substitute the missing aeccland.shx with a generic font (usually simplex.shx or txt.shx). The result is catastrophic for drawing fidelity: aeccland.shx
aeccland.shx is a compiled shape file (hence the .shx extension) developed by Autodesk. It is specifically associated with Autodesk AutoCAD Architecture (formerly ADT - Architectural Desktop).
Unlike standard text fonts (like txt.shx or romans.shx), a SHX file can contain two distinct things:
In the case of aeccland.shx, the file serves a dual purpose within the AutoCAD Architecture environment: The most frequent reason people search for this
This is a critical legal point. aeccland.shx is copyrighted intellectual property owned by Autodesk, Inc.
Warning: Many "free SHX download" websites offer this file, but they often bundle malware or outdated versions (pre-2007 format). Never download SHX files from untrusted third-party sources.