"Open With" list has everything double!

[Millwood]

I was wondering if someone can help me, when I right click on an item and use the "open with" tab, everything is listed twice. I was wondering how to fix this, this just occured within the last 2 days and i'm not sure what I could have done to cause it.
Here's a screenshot of what I mean:

Thanks for anyone who can help!

 

[yellow]

http://www.macosxhints.com/article.php?story=20031215144430486

 

[redeye be]

https://forums.macrumors.com/threads/195575/

 

[Eidorian]

A lot of the maintenance programs for OS X rebuild LaunchServices.

http://www.apple.com/downloads/macosx/system_disk_utilities/maintenance.html

My favored program. I had a really bad experience with OnyX.

 

[Millwood]

Thanks for the quick reply guys! i'll try them out, thanks so much! (That maintenance one wouldn't be the same as running macjanitor would it?)