[Forum] Upgraded from 3.8 to 4.0, unable to post/edit/etc

[michaelcastello]

I recently upgraded from vBulletin 3.8 to 4.0. Everything looked great afterwards, but when I tried to make a post, I discovered that something was wrong. I can't "do" anything from the front-end, such as writing threads or posts, or pinning topics, etc. When I try to edit/write a post and hit Submit, it gives me a completely blank page (nothing in View Source, even though it returned 200 OK). If I try to do something from the "Moderation tools" dropdown (on a thread list or inside a thread), it tells me "Invalid action". I don't have any problems just looking at the forums, though.

I can do everything in the back-end (AdminCP), but that doesn't do my users any good. The site worked fine before the upgrade. If I upload the forum in a separate directory and create a new database, everything works, but losing the whole database isn't an option. I've even tried using a backup (from 5 days prior to the upgrade) and migrating from there, but I still have the same issue. And I've gone through the list in Maintenence -> Suspect File Versions, and it doesn't seem to notice anything particular odd.

# php -v
PHP 5.2.0-8+etch11 (cli) (built: May 10 2008 10:46:24) 
Copyright (c) 1997-2006 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2006 Zend Technologies

# mysql --version
mysql  Ver 14.12 Distrib 5.0.32, for pc-linux-gnu (i486) using readline 5.2

I have absolutely no idea what's going on at this point. Any help would be appreciated!

[michaelcastello]

We're still dealing with the same issues after several more attempts to upgrade. We've reinstalled 3.8 to a separate location, and imported a previous backup, which works completely. It just doesn't make sense that a perfectly functional database could stop working, especially after several attempts to migrate.

[Zachery]

Is error reporting on in PHP, if this is a dedicated server, do you have any security products: mod_security, suhosin?

[michaelcastello]

nashville.com/forum4

Is error reporting on in PHP, if this is a dedicated server, do you have any security products: mod_security, suhosin?

We have a dedicated server from Rackspace. Error reporting is on. There was no error logfile set and display_errors was off, but I toggled display_errors and restarted Apache. Still no output when I try to make a post, and I can confirm that display_errors is On from the AdminCP.

I don't believe we have mod_security or suhosin.

[michaelcastello]

I just ran the compareutility.php utility to check the database, and it looks clean. There are three fields that are marked as "missing", however:

holiday
varname
[Ask for Query]	

subscription
varname
[Ask for Query]	

usergroup
albumpicmaxsize
[Ask for Query]

Are these that integral to every operation from the front-end? It doesn't make sense that the AdminCP can do anything with the database, yet in the front-end I can't do even the simple operation of editing an existing post.