InDesign guards your data against unexpected power or system failures using an automatic recovery feature. Automatically recovered data exists in a temporary file that is separate from the original document file on disk. Under normal circumstances you don’t need to think about automatically recovered data, because any document updates stored in the automatic recovery file are automatically added to the original document file when you choose the Save or Save As command or exit from InDesign normally. Automatically recovered data is important only if you’re unable to save successfully before an unexpected power or system failure.
Even though these features exist, you should save your files often and create backup files in case of unexpected power or system failures.
If automatically recovered data exists, InDesign automatically displays the recovered document. The word [Recovered] appears after the filename in the title bar of the document window to indicate that the document contains unsaved changes that were automatically recovered.
If InDesign fails after attempting to open a document using automatically recovered changes, the automatically recovered data may be corrupted.
To save the recovered data, choose File >Save As, specify a location and a new filename, and click Save. The Save As command keeps the recovered version that includes the automatically recovered data; the word [Recovered] disappears from the title bar.
To discard automatically recovered changes and use the most recent version of the document that was explicitly saved to disk before the failure occurred, close the file without saving it and open the file on disk, or choose File > Revert.
If necessary, you can cancel a lengthy operation before it’s completed, undo recent changes, or revert to a previously saved version. You can undo or redo up to several hundred of the most recent actions (the amount is limited by the amount of RAM available and the kinds of actions you performed). The series of actions is discarded when you choose the Save As command, close a document, or when you exit from the program.
To undo the most recent change, choose Edit > Undo [action]. (You cannot undo certain actions, such as scrolling.)
To redo an action, choose Edit > Redo [action].
To undo all changes made since the last time you saved the project, choose File > Revert (InDesign) or File > Revert Content (InCopy).
To close a dialog box without applying changes, click Cancel.
There are multiple factors, both internal and external to InDesign application, that can lead to document corruption.
InDesign has an auto-repair mechanism that detects and automatically recovers a corrupted document. The recovered version of the document will open in InDesign prompting you to save the document before proceeding further.