"SafeFileOpen"

"SafeFileOpen" is an option for notebooks that determines if Mathematica should take any special precautions before opening a notebook.

With the setting "SafeFileOpen" IgnoreCache, Mathematica ignores the file outline cache when opening a notebook. The file outline cache contains information about the structure of the notebook and reduces the time taken to open large notebooks. With the IgnoreCache setting, you can open a notebook even if its file outline cache has become corrupted. This setting has the same effect as the File Open Special menu command with the File reading method set to "Ignore File Outline Cache."

With the setting "SafeFileOpen" Prescan, Mathematica scans the expression for each cell in the notebook to confirm that it starts with the text Cell[. This is a quick way to check for one common sign of file corruption.

With the setting "SafeFileOpen" None, Mathematica does not take any special precautions before opening a notebook. Use this setting if you want to minimize the time taken to open a notebook.