So, usually this occurs when you don't have the AutoCAD font path correctly defined in your system. the first thing to check in all versions of AutoCAD is the path - I don't have LT, but it will be similar.
From the command line, type OPTIONS, or OP, and press enter. You can also access options by clicking the Right Mouse button over the command line, and then selecting Options.
Once the dialog is open, select the Files tab.
On this tab, scroll down until you see the support Files search path.
You need to make sure you have a path similar to this:
C:\Program Files\Autodesk\AutoCAD 2015\fonts
If you don't, then locate and add this folder by selecting the Add button on the right side of the dialog.
Select apply to save the changes, or OK to exit the dialog.
If you do have this path, but still get this error, it means the font being used in the drawing is not located in one of the support file paths. Check with the person who sent you the file, and make sure they include any special fonts that have an SHX file extension. Make sure you copy the font files to the file location you looked at earlier.
Also, check this folder and make sure it isn't empty, using Windows File Explorer. If it is, I would simply reinstall the program from the Control Panel > Programs and Features tools. You can reinstall the software pretty easily from there.
If this doesn't fix the problem, see if you can find out the name of the font file (.SHX) and the name of the style that's looking for the font. It should appear in the error message when you open the file.
thanks - David B.
David A. Butts
Virtual Design and Construction Manager - Kimley-Horn
Revit Certified Professional/Autodesk Certified Instructor
Revit, AutoCAD Architecture, MEP, Plant 3D, BIM Collaborate Pro Subject Matter Expert
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