The files that Sweet Home 3D tries to recover at its start have a .recovered extension and are stored in the C:\Users\userrecovery subfolder that you can find in a private folder that depends on your system:
- C:\Users\user\AppData\Roaming\eTeks\Sweet Home 3D under Windows Vista / 7/8/10,
- C:\Documents and Settings\user\Application Data\eTeks\Sweet Home 3D under Windows XP and previous versions of Windows,
- Library/Application Support/eTeks/Sweet Home 3D of your user folder under Mac OS X,
- Library/Containers/com.eteks.sweethome3d.SweetHome3D/Data/Library/Application Support/eTeks/Sweet Home 3D of your user folder under Mac OS X Mac App Version,
- .eteks/sweethome3d of your user folder under Linux and other Unix,
- data of the folder that contains Sweet Home 3D applications under the portable version.

Under Mac OS X, to ensure you pick the right eTeks folder, you can open a new window in the Finder, select Go > Go To Folder menu item (cmd + Shift + G shortcut), and enter the folder ~/Library/Application Support or ~/Library/Containers/com.eteks.sweethome3d.SweetHome3D/Data/Library/Application Support/eTeks/Sweet Home 3D.

If you don't mind, please [url=mailto:[email protected]]send me[/url] the .recovered file that caused your issue. When a recovered candidate file can't be opened, it's supposed to be renamed with a .unrecoverable extension to avoid the loop bug you encountered. If I can find how to detect the problem in your file, I'll fix this mechanism.