The ASF (Advanced Streaming Format) is an audio and video container specially designed and used for streaming. If you usually download videos in this format, AsfTools is the tool that you've been looking for. You'll be able to join two or more videos into a single one, divide files into various parts or recode files.
AsfTools also allows you to repair the videos that may have become corrupt due to various reasons. Another function that AsfTools offers is to add a search bar to the videos, because many of the files that come from streaming don't offer you the possibility to move the image forwards or backwards. And last of all, with AsfTools you'll be able to convert these formats to AVI or WAV in a very simple way.
Try out AsfTools and manage ASF files without any problems.