I am using : version 1.4.1.6 [8326](fresh install) and when I click log out in the admin area, I am taken to /zp-core/admin.php?logout=0 and get the following php message :Catchable fatal error: Object of class __PHP_Incomplete_Class could not be converted to string in {MYDOMAIN|/zp-core/lib-auth.php on line 714

Could you please check and see what that line reads in your copy of lib-auth.php? The copy I have reads $candidate = array_unique($candidate); so I see no way it could generate the error you show.

sbillard - my reads the same as yours

$candidate = array_unique($candidate);

I have never seen an error like this before.

let me try clearing my cache and restarting my browser again. Should I try session management rather than cookie based?

When I was trying the admin in internet explorer, the logout works properly. But it still does not work in Firefox

Does the error happen only with Firefox? That would really be strange since the code is server side. But maybe there is a problem with Firefox cookies.

I think there is an issue with Firefox cookies here. It works properly now that I have cleared cache

Thanks

Ok, keep us posted if the problem comes back.