When trying to open a DXF file in AutoCAD, an error is reported:
Error in drawing header on line 1.
Invalid or incomplete DXF input -- drawing discarded.
Press ENTER to continue:
This error indicates that the opened DXF file is corrupted (damaged). Common causes are:
- The DXF file was created by an external application but it doesn't have a proper format matching the DXF specification.
- The file was created as an export from a corrupted (e.g. non-Autodesk) DWG file.
- The file was damaged during transmission or during copying.
- It is not a DXF file, but e.g. a renamed .DWG file.
- The DXF file was edited in Word.
- The DXF file is not stored in the ASCII or UTF-8 (w/o BOM) format - it is stored e.g. in the text format encoded as UTF-16 or as UTF-8 with the leading BOM characters.
Try to create the DXF file again or repair it using a text editor, e.g. Notepad, Notepad++.
A typical DXF file (after you open it in Notepad) begins e.g. with this:
0
SECTION
2
HEADER
9
$ACADVER
1
AC1032
9
$ACADMAINTVER
90
157
9
$DWGCODEPAGE
3
ANSI_1250
9
$LASTSAVEDBY
...
The error may be found also on a higher line number - in this case, it is typically a syntax error in the DXF exchange format on the given row. Or the file comes from a higher AutoCAD version than you use to open it. Correct the problem in a text editoru or contact your AutoCAD vendor.