Editor seems to be missing a component

So, I try to open up my editor and it says something like ''Program can't start because DSOUND.dll couldn't be found."
Is there a way to fix it?

Sounds like a DirectX problem. Does Knytt Stories work (with sound) instead? If it does, maybe the editor executable is corrupted or something, so you should try redownloading Knytt stories.

If neither works, you should probably try some of the solutions pointed out here (about.com link).