How to Recover Crashed or Unsaved AutoCAD Files (.bak, .sv$, Autosave)

Losing work after a crash is part of the job. What matters is how fast you recover it. AutoCAD leaves multiple traces—if you know where to look and in what order.

ATTENTION — Read Before Doing Anything

Do NOT restart your computer and do NOT close AutoCAD sessions unnecessarily before checking recovery files.

Some systems or cleanup scripts will wipe the Temp folder on reboot, which permanently deletes .sv$ autosave files.

First step: secure your recovery files.

Quick Recovery Checklist (Use This Order)

• Run DRAWINGRECOVERY
• Search for .sv$ files in %temp%
• Try the .bak file
• Use RECOVER / RECOVERALL
• Check cloud or previous versions

Drawing Recovery Manager (Primary Method)

After a crash, AutoCAD usually opens this panel automatically.

• Command: Type DRAWINGRECOVERY if it does not appear
• What it shows:
  • .dwg (original)
  • .bak (backup)
  • .sv$ (autosave)
• Action:
  • Open the file with the latest timestamp
  • Save it immediately as a new .dwg

This is always the cleanest recovery path.

Recover from Backup Files (.bak)

AutoCAD creates a .bak file at each manual save (QSAVE). It represents the previous saved state.

• Open the folder containing your drawing
• Locate the .bak file (same name)
• Rename .bak → .dwg
• Open it in AutoCAD

You typically lose only the last save cycle.

Recover from Autosave Files (.sv$)

Autosave files are temporary backups created at intervals.

Locate Autosave Files

• Windows:
  • Press Start → type %temp%
  • Or check: Options > Files > Automatic Save File Location
• macOS (reliable method):
  • In AutoCAD command line, type: (getvar “SAVEFILEPATH”)
  • This returns the exact autosave location (recommended over guessing paths)

Recovery Procedure

• Look for files like: Drawing1_1_####.sv$
• Copy the file to Desktop
• Rename .sv$ → .dwg
• Open in AutoCAD

Important Behavior (Often Missed)

• Autosave only triggers when AutoCAD is idle
• If AutoCAD is frozen during a heavy command, no autosave occurs
• If AutoCAD is open but unresponsive, the .sv$ file may be outdated

This explains many “I lost 20 minutes of work” cases.

Repair Corrupted Drawings

If the file exists but won’t open or behaves incorrectly:

• RECOVER
  • Repairs the selected drawing file
• RECOVERALL
  • Repairs the drawing and all attached Xrefs
  • This matters: a corrupted Xref often crashes the host drawing
• AUDIT
  • Run inside an open drawing
  • Type AUDIT → Y to fix database errors

Alternative access:

• File > Open → select file → dropdown → Open and Repair

Windows Power Tip — Find All Autosave Files Instantly

Instead of browsing folders manually:

Open Command Prompt and run:

dir %temp%\*.sv$ /s

This lists all .sv$ files recursively, which is much faster on large systems.

Check Windows Previous Versions

If your file is on a local drive or server:

• Right-click file or folder
• Select Restore previous versions
• Choose a snapshot

Works only if System Protection or File History is enabled.

Check Cloud Backups (Autodesk / OneDrive / Google Drive)

If you work in synced environments:

• OneDrive → Version History
• Google Drive → File → Version History
• Autodesk Docs → Version panel

This is often the only option after a full reboot.

Expert Configuration (Reduce Risk Going Forward)

About ISAVEPERCENT (Critical)

• Default (20) = incremental saves
• Faster, but riskier if crash occurs during write
• Setting ISAVEPERCENT = 0 forces full file rewrite every time

This significantly improves recoverability.

About MOVEBAK (Clean Project Folders)

Use MOVEBAK to redirect .bak files to a dedicated folder:

• Example: D:\CAD_Backups
• Keeps project directories clean
• Maintains full backup history

Common Failure Cases (Real-World)

Drawing Recovery Manager shows nothing

• Check %temp% manually
• Verify autosave path
• Search entire drive for .sv$

No .sv$ files found

• Autosave may be disabled
• Temp path may be redirected (IT / network)
• Autosave didn’t trigger (see idle behavior)

Recovered file is incomplete

• Try older .sv$ versions
• Try .bak file
• Check cloud history

File crashes AutoCAD on open

• Use RECOVER instead of OPEN
• Try RECOVERALL (Xrefs issue)
• Disable hardware acceleration

Practical Recovery Workflow (What Actually Works Fast)

1. Run DRAWINGRECOVERY
2. Open latest file → Save immediately
3. If missing → search %temp% for .sv$
4. If nothing usable → use .bak
5. If unstable → run RECOVER / RECOVERALL
6. Final fallback → cloud or previous versions

Note on .ac$ Files (Do Not Rely on Them for Recovery)

You may see .ac$ files in temporary folders and assume they can be used for recovery.

That is not the case.

• .ac$ files are temporary working files used by AutoCAD for:
  • Undo/Redo operations
  • Internal calculations
  • Session buffering
• They do NOT contain a full DWG database
• They cannot be converted or renamed into usable drawings

Do not waste time trying to recover data from .ac$ files. Focus on .sv$, .bak, and proper recovery commands instead.

External References

• Autodesk Help (AutoCAD): https://help.autodesk.com/view/ACD/
• Autodesk Knowledge Base (Recovery): https://knowledge.autodesk.com/support/autocad

FAQ — AutoCAD File Recovery

How do I recover an unsaved AutoCAD file?

Run DRAWINGRECOVERY first. If nothing appears, go to %temp%, locate a .sv$ file, rename it to .dwg, and open it.

Where are AutoCAD autosave files stored?

• Windows: %temp%
• macOS: use (getvar “SAVEFILEPATH”) to get the exact path

What is the difference between .bak and .sv$ files?

• .bak: previous manual save
• .sv$: automatic temporary save

Can I recover a file after restarting my computer?

Sometimes. Autosave files may be deleted, but:

• Check temp folders anyway
• Use cloud version history
• Use Windows Previous Versions

Why is my recovered file corrupted?

The crash likely occurred during a write operation. Use RECOVER or RECOVERALL to rebuild the drawing database.

Can I recover overwritten AutoCAD files?

Yes, if:

• Versioning is enabled (cloud or Windows) Otherwise, recovery is unlikely.

Why didn’t autosave capture my latest work?

Because AutoCAD was not idle. Autosave only runs when the system is temporarily inactive.

How do I prevent data loss in AutoCAD?

• Set ISAVEPERCENT = 0
• Keep ISAVEBAK enabled
• Use SAVETIME = 10–15
• Work with versioned storage (cloud or server)

This approach reflects how recovery is handled in production environments. Speed and order matter more than anything—check the right locations before anything gets overwritten.