Importing Video for New transitions in LSP

[Superman]

Does anyone know how to do this?.
I have some .AVI on my computer that will work but if I try and convert a video file to an AVI to make a new one I get "there is a problem with video file or format".

Is there a converter or step by step procedure I should be following?.
Currently I'm using freemake or windows movie maker.

 

[Superman]

Problem solved.
Thanks Kel and Beacy for your help in chat.
I went with Any Video Converter

 

[kel]

Gee, does that count as a post for me ... lol