MySQL Table Update when a user registers for the forum?

[shellx]

Hello,
I added some custom code of mine to one of the signup php scripts that a user would fill out when they wanted to signup to be a member on our vB board. The trouble was was that it would update my "login" mySQL table in another datbase, however it would then return an error to the user, and not update them in the vBulletin membership tables (it partially adds them). If anyone has done this succesfully and would be able to tell me where i should place my code (which file, which area, etc), it'd be helpful.

I get the following error when I try to update:

Invalid SQL: INSERT INTO userfield (userid,field1,field2,field3,field4) VALUES (46,'','','','')

Thanks