Recovering lost video on computer?

While trying to save my edited video using AVI video, my computer stopped saving and said that there was an error. After hitting debug the program closed out and I lost the video I had worked so long on. So to try and retrieve the video, I've installed Recover My Files. It found my lost doent but when I try to save it, it asks for a username and license key. I'm only using the free trial so I was never given that information. Does anyone happen to have them or can tell me how I can get them? What are some other free softwares I could download to recover my video besides Recuva or Recover My Files?