PGP File Decryption Failure When Using the Elliptic-Curve Diffie–Hellman (ECDH) Key Pair
If using an Elliptic-Curve Diffie–Hellman (ECDH) key pair to encrypt/decrypt
                a file, you must use the Modification Detection Code (MDC). Otherwise, decryption
                fails with a null:Application Error error at runtime.
               
If you see this error in the activity stream at runtime
                                during decryption and you are using EDCH keys, you have two
                                        options:
                     
                  
                  - Regenerate your PGP keys using RSA, and then use the RSA keys for encryption/decryption.
- Enable MDC during encryption of the file
                                                when using EDCH keys by selecting the
                                                  Include Modification Detection
                                                  Code checkbox on the Operations page
                                                of the Adapter Endpoint Configuration Wizard. 
This MDC requirement applies even if the file is being encrypted by a third party.