It's possible you installed the plug-ins in the wrong folders, or have several extra copies somewhere.

Do Help - About Plug-ins... in the Photoshop menus.

Do you see Camera Raw more than once?  Is the version showing as 7.1 there?

-Noel

There should be one more Camera Raw… at the top of the list, above CompuServe.GIF so it seems that ACR isn’t installed for CS6.

How did you install ACR 7.1 for CS6:  Help / Updates inside PS, from www.adobe.com/downloads/updates/ and downloaded then ran the installer, or did you hack things around a bit?  Have you restarted PS and/or restarted your machine since updating?

On a 64-bit system the two plug-in locations are:

C:\Program Files\Common Files\Adobe\Plug-Ins\CS6\File Formats\Camera Raw.8bi

C:\Program Files (x86)\Common Files\Adobe\Plug-Ins\CS6\File Formats\Camera Raw.8bi

On a 32-bit system only the first one exists.

You might try checking your system with the Adobe Support Analyzer that checks the install logs and sometimes tells you what is wrong:

http://www.adobe.com/support/loganalyzer/

There is a more manual installation processes:

http://www.adobe.com/products/photoshop/extend.html

For dyed-in-the-wool system gurus, it's actually possible to copy files out of the provided zip file and put them in the proper folders (some of which you have already identified).  I have a post or two on this forum detailing more info about that somewhere.

Keep in mind there are two separate plug-in files for 32 and 64 bit operation.  Paths with (x86) in them are for 32 bit.

-Noel

You’ve done half of the hacker install—what Noel gives the complete version of somewhere else in the forum messages.  There are both 32-bit and 64-bit versions of the plugin, and you  probably want both since you may not always be in the 64-bit application.   You need to extract each from the appropriate place in the patch zip file.  I think one is 1003 and one is 1002---you can easily tell which is which from the size compared to everything else.