(.shx is also a compiled shape/font file used by AutoCAD):
In the AutoCAD ecosystem, .shx files are vector-based files that define either text fonts or shapes used in complex linetypes. Specifically, aeccland.shx is part of the object library. aeccland.shx
Users often think, "Why is my CAD asking for a font? I just want to see the lines." aeccland.shx
A: Only if you no longer use or receive any drawings created with AutoCAD Architecture. Deleting it will cause errors on older files. aeccland.shx