I downgraded back to Snow Leopard after I was unhappy with Lion, I backed up all my filed with time machine to my external HDD before I downgraded. I reformatted the mac HDD with a clean install of SL. Once this was complete, I was not able to restore my files from my HDD using time machine, so I imported them all manually. Everything looked fine, but when I went to rename any of my pictures, videos or music, it required authentication and authorization for permission to change the files or there location within my mac. I ran disk utility from my install disk, and performed a permission repair, and disk repair from the install disk. Did not work. I re-upgraded back to lion to see if this would help and fix the issue, since there as no issue in lion before i downgraded. I was wrong, I am still having an issue every-time i try to move a picture,video,document, music from my files to another location, or modify them. Can anyone please help? Thank you so much in advance!