Or it could be that the video you have downloaded from the Internet is incomplete or missing a part.
AVI Previewer is a tool that can fix errors in damaged AVI files so they can once again be viewed in your player.
The success rate in the program varies between 70% and 80%, so success is by no means guaranteed.
The full version of AVI Previewer lets you know the precise errors that have occurred in the AVI file and gain access to the existing index in the AVI file header.
15 day trial version with certain features disabled. Maximum file size is 180MB.