Hi, welcome to the Magix forums.

First, please read this post and give us all the information requested there, especially about your computer and the exact version of MEP you have, check under Help>About. It is very possible that "MEP 15" is actually rather old now.

As a general rule, if MEP tells you you need a different codec it will also allow you to buy/download that codec direct from the Magix server. So, how are you receiving the message that a codec is needed? And which codec is it? Or are you using an "unusual" video file format which needs an equally unusual codec? If so, it is possible that MEP will still not be able to use it if it cannot "see" it as installed on your machine.

Jeff
Forum Moderator