Unable to add cookies, header already sent

Had a report of this a few hours ago. Seems like not logged in gets a message like this on threads:

Unable to add cookies, header already sent.
File: /home/goteams/public_html/forum/showthread.php(97) : eval()'d code
Line: 2

vBulletin.com seems to be down which doesn't help. Best I can tell this seems to be a problem casued by plugins or hacks.

I *think* the only thing we did recently was to swap out an adsense ad for a different advertisement in the threads. Trying to get a hold of my programmer for this.

Any suggestions since I'm not as techie as I'd like to be? Can somebody help point me in the right direction?


Added: I'm able to view some of the older threads while not logged in but nothing recent. Any ideas?

90% of the time when its an eval'ed code error, it is a plugin/product that is failing.

line 97:
($hook = vBulletinHook::fetch_hook('showthread_start')) ? eval($hook) : false;


go to your plugins manager and see what is attached to that showthread_start hook; try disabling them one at a time.

Got it, thanks. I'll update in a bit.