Hi. Because the forum you originally posted in is for beginners trying to learn the basics of Photoshop, I moved your question to the Adobe Camera Raw forum for specialized attention to your situation.
Have you recently upgraded or changed computer or user account? There are no Camera Raw presets by default, so the ones you had must have been added at some time. You need to add them again, but bear in mind that some of them may not work properly with Process 2010 (the default process in CR6) or Process 2012 (the default process in CR7).
On my Windows 7 computer, my presets are stored here: