I had the same problem and found an answer over at vBulletin.org that seems to work with a few exceptions;
Open your config.php in your includes folder of vBulletin and look for this:
PHP Code:
// Prefix that all vBulletin cookies will have
// For example
$cookieprefix = '/';
You're looking to see what the Cookieprefix is set to, mine was set to 'bb', but that's what I chose when I installed vBulletin.
Change your cookie prefix in coppermine to what you have your vb cookie prefix set to. That should do the trick.
If you don't have your cookie prefix set in your config.php then set it to whatever you have set in your vbulletin options and make sure that coppermine's cookie prefix matches in the vBulletin30.inc.php file.
The problem I ran into is when in Coppermine, if you click on memberlist, it takes you to the vBulletin AdminCP login page and if you click on 'logout' while in Coppermine, it takes you back to vBulletin, but you get the "An error occurred while attempting to log you out." error. Hopefully someone can come up with a solution for these problems..
I have the same problem. I switched to the vbulletin30.inc.php file for the bridge and entered the 'bb' as the cookie prefix.
However, I still have the same problem. In the define statement for My vbulletin directory, I placed a '/' .
It just loops Me to the main page of the forum
When I change the define statement from '/' to '/gallery/' where I keep My gallery, I get a redirect timeout when I try to log in.
In all cases, the gallyer will not recognize any of My registered usernames as legitmate users and I can't even get back into the admin panel. I'm going to delete the entire coppermine tables in the database and work on a clean install once more.
Obviously, the bridge was not well thought out as too many people are not having good experiences.
The question that needs to be asked its this:
Before intergration, does the coppermine gallery need to be set up precisely to the vbulleting in terms of usergroups, users and permissions BEFORE intergration?
Any help would be greatly appreciated.