All of a sudden we just got an error after doing nothing to the database? It happened randomly with this error: Fatal error: Call to undefined function mb_regex_encoding() in /home/mccombpo/public_html/codelib/slib/CMBStr.inc.php on line 30

Something horrible must have happened to your PHP. Maybe, somebody messed up php.ini? By the way, when a harddisk of your web server is full, PHP tends to behave crazy. You may want to check if your harddisk has enough space.