Photoshop Disk Error - please help!

I have Photoshop CS2 installed on my MacBook, and I am using Mac OSX Version 10.6.8 My photoshop was working perfectly yesterday but today when I try to open files it comes up 'could not complete the open command because of a disk error' and also when I try to save, the same message appears. Please help, I really need to use Photoshop urgently! I installed updates this morning and restarted my mac, could this be what has caused it? Thank you

Yes, I think 7.3 is currently pulled due to the problems its caused. Do you have a backup?

Thank you, no unfortunately not, and I no longer have access to the disk. Thanks for you help though!

This is probably the update, check your Software Update again to see if the fix is now available.