[markbolyard]

I believe your problem is that one of your templates has code in it for vbadvanced, but you do not have vbadvanced installed.

To verify this, view your forum with the default vbulletin skin (no template edits at all). If you do not have errors, then it's most likely the skin you are using. You could try downloading the skin from http://www.vbskinworks.com (assuming you purchased it there you should be allowed updates)

PS: vba_cmps_plugin_newpost.php is NOT a vbulletin stock file. It's part of http://www.vbadvanced.com. I mention that because if you know you didn't install it, perhaps someone tried, and never finished.