How do you convert a video that has been encoded to an FLV file?

I accidentally encoded a video to an FLV file, without keeping a duplicate. Now i can't put it on youtube. Is there a program that I can use to convert it back? I always use moyea flv to vidoe converter, it is able to convert flv to avi, flv to video, flv to mpeg, flv to wmv, flv to mov, flv to mp4, flv to mp3,flv video converter flv to 3gp, Add logos or text as watermark for the generated video files, trim video.I have used it for a long time, it works great for me, if you need, you can free download it here to have a try,