Does this issue occur with just this drawing file, or with any file? Does this issue occur on other workstations? Please provide us with the file. Have you tried to recover the file from the AutoCAD Application. Close all open drawings (Be in a Zero-document state). Go to the Application Menu (Big A, Top Left Corner) > Drawing Utilities > Recover.
Joshua Benoist, PE Senior Support Specialist Product Support Autodesk, Inc.