Cannot open some jpgs in Camera Raw from Bridge

Question

A couple of days ago, I rated select images from a set as 5 stars, and now I cannot open these in Camera Raw from Bridge. I get no error messages or anything, there is just simply no option to Open in Camera Raw from the File menu, or the right-click menu. The images I did not rate still open in Camera Raw, and not all of the starred ones have this problem - just 20 or so consecutive images. This makes no sense to me, as all the images as far as I can tell should operate the same way. They are all jpgs. I can find workarounds to this like working in Photoshop (all the images still open in Photoshop) or possibly just reloading the photos from the memory card, but I'd like to know why this would even be a problem to avoid it in the future. I'm using CC on Win 8.

Answer 1

I should add that JPGs edited with ACR usually need to be writable for ACR to be able to store the adjustment-settings inside themselves.  RAW files typically use an XMP sidecar to store settings, but JPGs typically don't.
If the files weren't read/write then ACR would have no way to store the adjustments in them and so is smart enough to not make them available for editing.
The other hint is that if you copy the files to your desktop--where the permissions are likely to be more friendly, they work.
To check the permissions, right-click on one of the files in Explorer, select Properties from the context menu and look at the Security tab.  Look at the various user-groups, like Users, Authenticated Users, Administrators, etc, and see what access each has to one oft he problem files, and then to one of the files that works ok.
You might also check the Effective Rights of a particular user to a particular file by clicking on the Advanced button in the Security tab.  Here is an example where I show only Read + Read & Execute access to an NEF for general users, but when I check my own logged in User (steve) I have Full Control which includes all the other access privileges, and this is either because I'm in the Administrators group or I am the owner, I'm not sure.  It is possible that Bridge or Photoshop is running in a user context other than your logged in user, or it's possible that another user accessed the files and changed the permissions to them.