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CAD tip # 5102:
Question
A
The error message "Drawing file is not valid" when opening a DWG file informs about a corrupted drawing file or a DWG format of a newer AutoCAD version.
Try to open the .DWG file in Windows Notepad and check if the file starts with AC10xx (see Tip 868). You may try to use the RECOVER command on the file, or INSERT it into an empty drawing.
DWG files may become corrupted as a result of virus attack, online transmission errors, disk/media errors, using unreliable AutoCAD clones, or by inadverent editing of their binary content e.g. in Word or Notepad.
ACADACLT


8.7.2006
134593×
FAQ
applies to: AutoCAD · AutoCAD LT ·