To convert the file you need to install Notepad++.
https://notepad-plus-plus.org/downloads/v7.9.5/
1-Open the Notepad++
2-Click on file>open and select the DXF file that you are receiving the error message.
3-Look up the UNDEFINED value under the $DWGCODEPAGE section. Replace this with the code page shown in the message prompt (ANSI_1252).
6-Save the file
5-Then open the file in AutoCAD and run the AUDIT command.
https://knowledge.autodesk.com/support/autocad/...(Command)%20%2D%20Evaluates%20the,and%20layers%2C%20from%20the%20drawing.
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