Database error in vBulletin 4.1.1
 

Database error in vBulletin 4.1.1:

Invalid SQL:

SELECT a.attachmentid
FROM attachment AS a
WHERE
(filedataid = AND userid = 3);

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 'AND userid = 3)' at line 4
Error Number : 1064
Request Date : Monday, December 24th 2012 @ 02:18:27 AM
Error Date : Monday, December 24th 2012 @ 02:18:27 AM

Kindly Provide solution how to correct it. due to this error i could not upload attachments

Try disabling your modifications/plugins and see if you still have this problem.
Note: To temporarily disable the plugin system, edit includes/config.php and add this line right under <?php

i m using following plugins do u suggest which of them could cause problem

Display Unread Posts and Reputation 4.1.7.0

Forum Category Icons (Advanced) 2.0.0

Inferno vBShout 2.5.2

Limited Guest Viewing 2.1.0
Members who have Visited 4.1.7.0
Top Posters 4.1.7.0

Usergroup Color Bar 2.0.0

vBSEO :: Sitemap Generator 3.0

VSa - ChatBox 3.1.8 VSa - ChatBox

VSa - Sub-Forum Manager 3.1.4

Who Has Read a Thread 4.1.7.0

I have no idea. Try disabling them all, see if the problem goes away, then add them back one-by-one to see which one makes the problem come back.