Can you please let us know the following information:
1. Please go to C:\Program Files (x86)\Real\RealPlayer.
2. Right click on videodl and click Properties and then the Details tab.
Please provide us with the version number you see there.
Can you also search for the same video using YouTube with a web browser and try? If it fails here too, could you please provide us with a sample URL that you are trying to download?