Hi there! Because the forum you originally posted in is for beginners trying to learn the basics of Photoshop, I moved your question to the Photoshop General Discussion forum, where you'll get more specialized help.
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Just reinstall the software.
And it sounds like you've deleted some files, or used the Migration Assistant and it failed to copy some files (it does that pretty often).
What I have discovered is that the migration from a 4 yr old MacBookPro hard drive to flash drive with retina display won't work.
I will have to buy CS6 or use Gimp which is free of course!
You probably just need to reinstall the software to get all the files (and reapply all the updates).
Again, the Migration Assistant frequently fails to copy all the files correctly.