Database error

[bosanci28]

Hello,

I am getting some emails with "Database error" message from my forum and not really sure why!

This is what i get:

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Database error in vBulletin 4.2.2:

Invalid SQL:
SELECT location, badlocation FROM session WHERE userid = n AND lastactivity > 0 ORDER BY lastactivity DESC LIMIT 1;

MySQL Error : Unknown column 'n' in 'where clause'
Error Number : 1054
Request Date : Wednesday, May 20th 2015 @ 10:36:02 PM
Error Date : Wednesday, May 20th 2015 @ 10:36:03 PM
Script : forum link it is in here....(deleted by me)
Referrer :
IP Address : xxx.xx.xxx.xxx
Username : Unregistered
Classname : vB_Database
MySQL Version :

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Ip address is changed all the time,in every email ! so i guess there are from different people.

Thank for any advice on this.
B.