I use VLC as my default video player because Windows Media Player doesn’t necessarily recognize all the formats. But I doubt installing DownloadHelper had anything to do with making VLC a default player. If the video is an mp4, then that may be why it’s related to VLC instead of WMP.
Yes, you should be able to change the default program for files. How depends on your version of Windows. I use Windows 7 and it’s straightforward. Opening the Start menu gives an option of ‘Default Programs’ in the right vertical panel. Clicking on that, then selecting ‘Associate a file type or protocol with a program’ gets the job done.
Hope you enjoy DownloadHelper.
Thank you again. Much obliged.