Comment 23 for bug 1178024

david2008uk, just use 'sudo synaptic' in a terminal to launch synaptic instead.

You could set the setuid bit on the synaptic executable so that it always runs as root, but you should NOT do this because this way you're creating a security vurnerability (everyone would be able to install anything).

It's better to just use regular sudo instead of gksu to launch synaptic. Also, you can create a launcher on your desktop with the 'sudo synaptic' command, for the ease of use.