Passing/Inserting Checkboxes

Hi everyone.

I have a very simple form with 36 checkboxes, one of which is initially checked. The other 35 are unchecked by default. I have created similar forms many, many times without an issue. For some reason, every time I submit the form, I get a 500 Internal Server Error. Here's what the code looks like for the checked checkbox, an unchecked checkbox, the action, and the insert:

Initially checked:

<input name="Email" type="checkbox" id="Email" value="-1" checked="checked" />

Unchecked by default:

<input name="Art" type="checkbox" id="Art" value="-1" />

Action code:

<cfif not isdefined("Form.Email")>
   <cfset Form.Email = "0">
</cfif>

<cfif not isdefined("Form.Art")>
   <cfset Form.Art = "0">
</cfif>

Insert code:

(Email,Art)

VALUES ('#Form.Email#','#Form.Art#')

I've tried everything, and like I said, I've built forms like this before without an issue. Any help would be GREATLY appreciated.