Extract Audio Stream not working? :S

[Northwind]

Heyo!

When i click ''Extract Audio Stream'' it's only pop-up ''How do you want to open this file? Use this app for all .avi-files''

It's the first time it have pop'd up to me, i don't know why.

OS Windows 8.1

Thanks.

[ExKoder]

reinstall Dxtory.
Still when not recovering, I don't know solution method.