From Autodesk;
Error: Internal Error: !DBUTIL.CPP@855 (the number can vary I think...)
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ID: TS38353
Applies to: AutoCAD LT® 2000,
AutoCAD LT® 2000i,
AutoCAD LT® 2002,
AutoCAD® 2000,
AutoCAD® 2000i,
AutoCAD® 2002,
Autodesk Field Survey
Published Date: 06/15/2001
Issue
When you open a drawing file, the following error message is displayed and you are unable to recover the file:
INTERNAL ERROR: !DBUTIL.CPP @855
Solution
The possible cause of this error is the infiltration of legacy DXF information from third-party applications. Legacy DXF information often renders files unrecoverable. There is no known resolution at this time. You can try to recover the files in an earlier release of the software, such as AutoCAD® Release14 or AutoCAD LT® 98, or you can try the recovery techniques documented in the related topic.
Good look
Pedro Treviño