Error in Admin CP > Users
 

That is caused by a modification.

To troubleshoot this, please remove any hacks and disable your plugins, then see if you still have this problem.
Note: To temporarily disable the plugin system, edit config.php and add this line right under <?php

define('DISABLE_HOOKS', true);

If so, reupload all the original vB non-image files (except install.php). Make sure you upload these in ASCII format and overwrite the ones on the server.

i have the following plugins installed

product-usergroupchangelog
product-namechangeusernote12
product-emailchangelogger

See post #2