Sansa Media won't convert

i need help, when i put a video in to convert it will go from 1 to 100 percent instantly and then it doesnt show up on the e250 and doesnt take up space. the video is 66mb and i have 1700+ mb free so i know thats not the problem.

does it play in hte preview box just fine? where did the video come from? do videos from other sources work fine?

it plays in the preview box fine, and the video came from a cd

so what about videos form other sources? Are you ripping the cd to the computer first, and saving the file on your hard drive? What format are you ripping it in and what program? If your dragging and dropping, its not gonna work. What if you convert the video without the player plugged in, is it the same result?

videos from other sources sometimes work, it was in an avi format so i could convert it, and the player is plugged in while converting

Uninstall any video codec packs you have, and then install K-Lite codec pack (Search google for it!) then try again