How can you fix file parsing error in real player converter?

I downloaded several videos that I wanted to convert for my mp3 player. Most of them didn't show up in the converter window after saying something about the file parsing error. As an experiment, I went to my library and just dragged each song I had downloaded into the converter window and for some reason it worked. I guess there's something that screws up when it goes to transfer the songs from the download window to the converter window.....so for now I'll just have to download and then add everything in manually....which sucks because it takes a while.