Quick answer
Copy the file first so you never touch the original. In AutoCAD, use RECOVER to open a drawing that won't open, or AUDIT to fix one that's already open. If it's beyond repair, fall back to the .bak backup or an autosave .sv$ file. In Revit, open a fresh local from central, or restore a previous version from the model's _backup folder or your cloud version history.
Before you do anything: don't overwrite the original. Make a copy of the corrupt file (and, for Revit, its backup folder) and work on the copy. Recovery attempts can make a bad file worse, so keep the untouched original aside — if one method fails, you'll want a clean starting point for the next.
WHY IT HAPPENS
Corruption is common — recovery usually isn't dramatic.
CAD and BIM files corrupt for ordinary reasons: a crash mid-save, working directly over a network share or a syncing cloud folder, a full disk, or a dropped connection to a central model. The good news is that Autodesk software is built expecting this. AutoCAD writes a .bak backup and periodic .sv$ autosaves; Revit keeps numbered backups and, for workshared models, a whole backup folder of previous versions. Most files come back with one of the steps below — the key is being methodical and never destroying your fallback.
HOW TO RECOVER IT
Work through these in order.
- Copy the file to a safe locationBefore any repair, copy the corrupt file (and its backup folder for Revit) to a separate folder — ideally on a fast local drive, not the network share. All the steps below run on the copy so the original stays intact as a fallback.
- AutoCAD: run RECOVER or AUDITFor a drawing that won't open, use RECOVER (Application menu → Drawing Utilities → Recover) to open and repair it. For one that opens but misbehaves, run AUDIT and answer Yes to fix errors. Use RECOVERALL if the drawing has attached external references, as it repairs those too. After a recovery, run AUDIT once more to confirm the drawing is clean before you keep working.
- AutoCAD: fall back to the .bak backupIf RECOVER can't save it, look in the same folder for a file with the same name and a .bak extension — AutoCAD's backup of the previous save. Copy it, rename the copy's extension to .dwg, and open it. You'll lose the changes since the last save, but you get a working drawing back.
- AutoCAD: check the Drawing Recovery Manager and autosavesAfter a crash, AutoCAD's Drawing Recovery Manager (DRAWINGRECOVERY) lists autosave and backup versions to restore. You can also find .sv$ autosave files in your Windows temp folder — rename one to .dwg and open it to recover work from between saves.
- Revit: open a fresh local from centralIf a workshared model is playing up, don't fight your existing local. Open the central file with Create New Local ticked so Revit builds a clean local from the current central. Often the central is fine and only your local copy was corrupt.
- Revit: restore from the backup folderA workshared central model keeps a folder beside it named <modelname>_backup containing previous versions. Copy that folder somewhere safe, then use Restore Backup (in the Collaborate/worksharing tools) to pick and roll back to an earlier, working version. Non-workshared files leave numbered backups such as project.0001.rvt in the same folder — open the most recent good one.
- Restore from version history or your backupIf the local tools can't rescue it, restore a known-good copy from SharePoint/OneDrive version history, BIM 360 / Autodesk Construction Cloud, or your business backup. This is why files should live somewhere that keeps versions — a plain network folder with no history leaves you with nothing to roll back to.
- Note the journal, then get helpRevit records what happened in its journal files — useful to your IT provider or Autodesk support for diagnosing repeat corruption. If nothing above recovers the file, stop before you exhaust your fallbacks and hand the original copy plus the journal to someone who can dig deeper.
If the same file keeps corrupting — or it happens across the whole team — the cause is usually environmental: files worked on directly over the network, a syncing cloud folder fighting the software, unstable storage or no proper backup. That's worth fixing at the source rather than recovering the same file every week.
