Is there a way to recover audio from a mic that was plugged in but didn't pick up sound.?

I recently interviewed someone on my DSLR with a lapel mic. I don't know if the battery is dead or what just yet, but I had the mic on and everything but all I hear is a humming sound, none of the interview. Is there anything that can be done about this?
Answers

Anonymous

Reinterview, Start over. There is nothing to "recover". You recorded nothing. Are you sure you plugged the mic into the right port? Are you sure the recording volume was on and turned up? You have now learned why people test "One, Two, Three,... Testing" before they use a recording or announcement system.

AVDADDY

Microphones don't store audio, the audio recorded by your camera is stored on the memory card along with the video. Given your description, it appears that no audio was recorded. There is no way to recover audio that was never recorded in the first place.

AlCapone

You can't recover something that is not there. Always test your setup before using it live.

M.

Go back in time. A microphone does not store sound. You must have a broken wire. That would explain the hum.

DR + Mrs Bears face

Hi so if is didn't work how do you expect to get any sound.

WHANKING-WILLY

You have a broken ground return, thus the hum. Are you really 'that' dumb?

spacemissing

No. Nothing was recorded, so there is nothing to recover.

don r

There is no help for that. A dead battery in a electret microphone is just like having no microphone.