Using Lightroom 4.4, I have many backup catalogs; each time I try to open one it shows as corrupted, and it the program is unable to repair any one of them. I believe I did something very stupid [with thanks to Norton Tech Support]: I deleted the appdata files, and I believe that is what's causing my problem. Does anyone have a solution? Because of computer changes, got caught in the middle, with no backup of the appdata files. Can I recover catalogs without the corresponding appdata?
each time I try to open one it shows as corrupted
Why do you say this? What exactly happens? If there is an error message, please quote the exact complete unedited word-for-word error message.
I am not really sure what "appdata" you are talking about, could you be more specific? Deleting any files on your computer will not cause Lightroom catalogs to be corrupted; the worst that could happen by deleting files is that Lightroom itself would need to be re-installed (depending on what files you deleted, of course). Of course, the corruption, if that's what you are seeing, could come from other possible causes.
Thanks for the response; happily, spent a lot of time, but I was able to recover the database. As best as I can tell, the appdata deletions did not affect the challenges. I just kept working at it, including the reinstall of Lightroom . . . and I recovered everything. Sorry, I should have posted, but I definitely appreciate your efforts to help.