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If Rhino is frozen and you haven’t saved your file recently, DON’T FORCE QUIT RHINO.
Instead, use the next step to look for the autosave file. Copy this file to someplace safe, then go back to Rhino and force quit it using the Task Manager.
Rhino usually autosaves a temporary backup periodically called RhinoAutosave.3dm.
Location in Windows: C:\Users\[username]\AppData\Local\McNeel\Rhinoceros\X.0\AutoSave\
Folder is hidden by default.
Don't open the file directly. Copy it to somewhere else like the Documents folder before opening.
Was the file originally opened directly from an email attachment (without downloading it first)?
Open Rhino and click File to see the list of recently opened files, along with their folder locations.
It may refer to a location such as C:\Users\[username]\AppData\Local\Microsoft\Windows\INetCache\Content.Outlook\E3XTHQXQ\.
Go to this folder using Windows File Explorer and you should see the missing files. Copy them to a different location such as the Desktop and then open in Rhino to check.
In the future, always save an attachment from Outlook first, and then open the saved file in Rhino.
Rhino saves a hidden backup file in the same location as the original.
Show hidden files to see. In Windows File Explorer, click the View tab and enable the checkbox for ‘Hidden items’.
Filename is the same as the original but ends in .3dmbak. Remove the bak to use (also change the filename slightly so as not to overwrite the original).
If the file was saved in OneDrive, right click the file and choose 'Version history'. Use OneDrive in the browser (https://onedrive.live.com) to do this if local doesn't work.
If the file was in OneDrive but was deleted, use OneDrive in the browser to look in the online OneDrive Recycle Bin.
Rhino displays a black screen or otherwise fails to load file or crashes.
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