gpg error

I am trying to decrypt a file using a given command line. i get the same error code each time:
gpg:Cast5 encrypted data
gpg: encrypted with 1 passphrase
gpg: decryption failed: bad key
Can anyone tell me what this means.

I’d love to know the same answer. I have the same issue. None of my keys are working. I receive the decryption failed error message.