After entering the Playstation Store I am unable to select any option or do any navigation. Only PS button works to quit the store. This happened before in early Dec 2012. I contacted support group who took me through a number of things. None of which solved the problem. It finally resolved itself about mid Dec, thru an update I guess,. It started again after downloading the latest update this week. System version 4.31.
Have you tried deleting then re-installing?
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Yes, I tried deleting and reinstalling. I do this every few days. I think that's how it finally resolved itself when it happened before. It took about 10 days of trying every few days. Just tried it again today without success.
Try online store heres a link, since you can sign in... make your purchase online, and then go to PS3 download from Transaction History/ Download list, and install.