Error when regsitering

[ctvtec]

I fixed the site working how i want it to work. I have one database error now coming to my email.. I guess its an error coming up to the members.

Here is the error:
Database error in vBulletin 3.8.1:

Invalid SQL:

SELECT post.userid, post.postid, post.visible, post.pagetext, user.usergroupid, post.icash
FROM post AS post
LEFT JOIN user AS user ON (post.userid = user.userid)
WHERE post.threadid =;

MySQL Error : You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 4
Error Number : 1064
Request Date : Tuesday, December 21st 2010 @ 11:41:01 PM
Error Date : Tuesday, December 21st 2010 @ 11:41:01 PM
Script : http://nyvtec.com/cron.php?&rand=203770
Referrer : http://nyvtec.com/search.php?searchid=965341
IP Address : 67.87.82.251
Username : Unregistered
Classname : vB_Database
MySQL Version :