.userdb error msgs

Logged in as admin and tried to make change in an album (tried to assign ownership to registered user and got the following:

Warning: unlink(/home/campmoon/public_html/Gallery/albums/jayne/serial.86.dat): Permission denied in /home/campmoon/public_html/Gallery/platform/fs_unix.php on line 83

Warning: fopen(/home/campmoon/public_html/Gallery/albums/jayne/photos.dat.lock): failed to open stream: Permission denied in /home/campmoon/public_html/Gallery/platform/fs_unix.php on line 55
Error: Could not open lock file (/home/campmoon/public_html/Gallery/albums/jayne/photos.dat.lock)!

Any thoughts?
Thanks.

http://www.campmoonbeam.com/Gallery

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