Tthe error message has been associated with a Autodesk Verision file (DLL). This file is related with Digital Signatures of files/drawings, and associated previews of the files in Windows. - the issue manifested in Acad products particularly in / since Acad 2004. The lilnk for dll file update is no longer active, what leaves the users with no option

The issue has been reported in Acad as well. Adesk suggested troubleshooting steps were: - File update (no longer feasible) - “When the application (AutoCAD) is installed, by default one of the .DLL file called as ' acSignIcon.dll' will be installed to the system directory. This DLL is related to the new drawing Digital Signatures that can attached to the AutoCAD drawing. If some problems occurred by this DLL file, you can search for the DLL and try to rename it to AcSignIcon.dll. Also try invoking the 'AcSignOpt.exe' and then uncheck the box; Validate digital signatures and display special icons. This will disable the special icon that file explorer shows for the digitally signed AutoCAD drawings.”