First you may read more resources are dedicated to mpp corruption
https://social.technet.microsoft.com...nal2010general
Save the file in the Microsoft Project Database format:
1. Open your problem file (it may help to turn off automatic calculation if the file is reluctant to open).
2. Select File/Save As...
3. Save as type: Project Database (*.mpd) then click Save.
4. Close the file.
5. Re-open it from the .mpd file.
6. Select File/Save As... and save it as an .mpp file again.