Recover the file
When a file has been corrupted, you can sometimes get the file back with its layers or as a composite (a composite is a flattened file). The appearance of the file is maintained, but the layers are lost. Or the file could be damaged beyond repair. Regular backups can allow you to salvage a version of your file that you saved before the corruption.
Note: A composite file cannot be recovered from a file when the option to maximize PSD and PSB file compatibility is turned off in Photoshop's preferences. To make sure that your files always save with a composite, do the following:
Choose Photoshop > Preferences > File Handling (Mac OS) or Edit > Preferences > File Handling (Windows).
Choose Always in the pop-up menu next to Maximize PSD and PSB File Compatibility.
Click OK to close Preferences.
Try any or all of these options to recover your file:
Use Save As to save the file to a new name in a different location. (For example, use an internal hard disk or a drive that is not a removable or network drive.)
Open any backed-up copies of your image to determine if one was saved before the corruption occurred.
If you've had one of these error messages, your filename extension may not match your file format:
Could not complete your request because it is not a valid Photoshop document.
Could not complete your request because an unknown or invalid JPEG marker type is found.
Could not complete your request because the file-format module cannot parse the file.
This is not a valid Portable Document File (PDF) document. It cannot be opened.
See Invalid JPEG marker error for the solution.
To open an image that contains damaged layer data with its composite, press Shift+Opt (Mac OS) or Shift+Alt (Windows) while your file is being opened. This solution doesn't work on all files.
Customers have suggested these recovery utilities. Adobe does not support them, and has not tested with them. However, we hope that they help recover your file.