What causes this error? The TargetControlID of <CheckBoxControlName> is not valid. The value cannot be null or empty
<p>I have searched on the net for this error, but there doesn't appear to be alot on it.</p>

<pre><code>The TargetControlID of 'CheckBoxControlName' is not valid. The value cannot be null or empty.
</code></pre>

<p>Does anyone know of the main causes for this error?</p>
