Recovering drawing files which fail to open in AutoCAD and verticals

Corruption can be introduced in numerous ways. Some examples are:

• Third-party applications running inside AutoCAD.
• DWG files created or saved by non-Autodesk or non-RealDWG products.
• AutoCAD terminated while saving the drawing.
• Old drawings used repeatedly over long time periods.
• Network anomalies (transmission errors, file locking, latent writing of data).
• Storage media degradation (bad sectors on a hard drive).
• Defective or failing RAM.
• Operating System issues.
• Power surges.
• Outdated software.
• 

1. Windows [Control Panel] -> [Folder Options] -> [View tab] ->(turn on the option to show hidden files).
2. Locate the drawing directory and delete the <drawingname>.dwl or <drawingname>.dwl2 files if they are found near <drawingname>.dwg file.
3. Attempt to open the DWG again.

• Run RECOVER on corrupt drawing file:
  1. Open a blank DWG and run the RECOVER command.
  2. Select the problematic file. AutoCAD attempts to recover the file.
  3. Open the recovered file.
• Run RECOVERALL on corrupt drawing file:
  1. Open a blank DWG and run the RECOVERALL command.
  2. Select the problematic file. AutoCAD attempts to recover the file.
  3. Open the recovered file.
• Insert the corrupted drawing as a BLOCK:
  1. Open a blank DWG and run the INSERT command.
  2. Select the problematic file.
  3. If it inserts, run EXPLODE and select the inserted block.
  4. Run an AUDIT command
  5. Run a PURGE command
  6. SAVEAS to create a DWG
• Recovering from a .bak:
  1. Locate the corrupted drawing directory or storage location.
  2. Find the .dwg file backup denoted by the .bak extension
  3. Rename the .bak extension to .dwg 
  4. Attempt to open the newly created file.
• Recovering from an autosave file (SV$):
  1. Locate the autosave folder location. (C:\Users\<UserName>\AppData\Local\Temp\)
  2. Find files with an SV$ extension. Find files with a similar name and different times or dates as compared to the corrupted .dwg file
  3. Rename the extension from .SV$ to .dwg.
  4. Attempt to open the newly created file.
• Try opening the drawing using DWG Trueview: 
  1. Convert the drawing Using DWG Trueview to an older DWG version.
  2. Attempt to open the newly created file.
• Look to a Shadowcopy (Windows Server) or TimeCapsule (Mac) archived versions from a time before the corrupted/current state.