This thread is gaping any details including the Mathcad Product and version you are working with and the corrupted file to fix.
Assuming that the file got corrupted through a Save command, you'd better look out for a backup file to use.
However, it is in some cases possible to recover a corrupted Mathcad Prime worksheet - even with restrictions. But any data fix and/or investigation from PTC R&D department needs a PTC case to be filed.
