Issues:
How to repair a damaged or corrupted AutoCAD drawing (.dwg) file. A drawing may have one or more of the following symptoms:
Drawing file does not open.
Drawing file opens with errors.
File hangs or crashes AutoCAD.
Slow performance when editing a file.
Error messages appear when working in a file.
Commands do not work or are delayed.
Unexplained increase in file size.
Display or regen problems.
Drawing elements missing or shown incorrectly.
Recovered version of the drawing opens but is blank.
Causes:
Third-party software is running within AutoCAD.
Non-Autodesk or non-RealDWG product created or saved the file.
AutoCAD terminated while saving a drawing file, such as during a power surge or outage.
Old drawings have been used repeatedly over a long time period.
Network anomalies have occurred (such as transmission errors, file locking, and latent writing of data).
Storage media has degraded (such as bad sectors on a hard drive).
System RAM is failing or defective.
Operating system issues exist.
First steps:
Can you open the drawing?