A recent Windows update or sudden system shutdown corrupted the .hdi file.
a specialized driver component used by older versions of AutoCAD to interface with the Windows Graphics Device Interface (GDI) autocad virtual device gdi16.hdi
If gdi16.hdi is from the 1990s, why does a modern computer even care? A recent Windows update or sudden system shutdown
Set the Variable value to (or Dx11 depending on your AutoCAD version to force it to use that specific engine). Click OK and restart your computer. Conclusion autocad virtual device gdi16.hdi