Due to the current unavailability of clairvoyants and mind-readers in this user forum, we respectfully request you supply sensible, complete details.
Note that because this is boilerplate text, not all points may apply to any given, specific poster.
If you give complete and detailed information about your setup and the issue at hand,
such as your platform (Mac in your particular case)),
exact versions of your OS, of Photoshop (not just "CS5.1", but something like CS5v.12.1) and of Bridge,
your settings in Photoshop > Preference > Performance
the type of file you were working on,
machine specs, such as total installed RAM, scratch file HDs, total available HD space, video card specs, including total VRAM installed,
what troubleshooting steps you have taken so far,
what error message(s) you receive,
if having issues opening raw files also the exact camera make and model that generated them,
if you're having printing issues, indicate the exact make and model of your printer, paper size, image dimensions in pixels (so many pixels wide by so many pixels high). if going through a RIP, specify that too.
someone may be able to help you (not necessarily this poster).
a screen shot of your settings or of the image could be very helpful too.
Please read this FAQ for advice on how to ask your questions correctly for quicker and better answers:
Did you check to see whether you have read and write privileges in the disk where you are trying to save?
Yes and I do
…but you're still not interested enough in getting assistance to provide pertinent information?
....if you could please be patient while i gather information sir/ma'am.
Save As with different file name.
None of the files are "locked". The issue is still happening on files that are not locked
You still have a permissions problem, most likely on the directory and not the files themselves.
Photoshop is just passing along the OS error about the files being locked, or you not having permission to write the files.