There are some restrictions on moving galleries (derived from the restrictions on the php rename function). Here's the relevant extract from the svManager docs:
You can change /svmanager/sporting-shots to /othergalleries/sporting-shots
In order for this to work:
The new gallery folder (sporting-shots) either must not exist or may exist and be empty.
Any folders above the gallery folder on the new path (othergalleries in the example above) must already exist. It doesn’t matter if they are empty or not.
The path to the new gallery folder should contain only alphabetic characters, numeric characters, hyphen, underscore, tilde and dot (no spaces).
In versions of svManager earlier than v1.4.0, all image and thumbnail files must be inside the gallery folder to be moved and must be named images and thumbs respectively. svManager always creates its galleries like this, so problems are only likely to arise with imported galleries. These restrictions were removed in svManager version 1.4.0.
If none of the above restrictions apply, then it's probably a permissions issue. You can get a more detailed error message which may help to pinpoint the problem by turning debug mode on. Edit svmanager/includes/constants.php and change the debug setting as follows:
// Set DEBUG to true for detailed error messages
Or you can just experiment with permissions on the relevant folders.
Incidentally, that looks like an old version of svManager.
SimpleViewer Support Team.