All of the callouts on my page just display the message "Control is not valid." I am not doing anything out of the ordinary, and here is a sample of how they are set up (Note that they are in a Modal popup):
```
<asp:TextBox ID="retrieveEmailFirstNameTextBox" runat="server" MaxLength="50" />
<asp:RequiredFieldValidator runat="server" ID="retrieveEmailFirstNameTextBoxRequiredFieldValidator" Text="Please enter your first name to proceed." ControlToValidate="retrieveEmailFirstNameTextBox" />
<asp:ValidatorCalloutExtender ID="retrieveEmailFirstNameTextBoxRequiredFieldValidatorCalloutExtender" TargetControlID="retrieveEmailFirstNameTextBoxRequiredFieldValidator" runat="server"></asp:ValidatorCalloutExtender>
```
Image showing behavior is attached.
I am using the latest version of the toolkit.
Comments: Hi. Is there a reason it cannot fall back to the text if the ErrorMessage property is not present - Or rather fall back to the ErrorMessage when the Text is not present? [The Text is the property the control itself uses when validation fails, whereas the ErrorMessage is used for the ValidationSummary control when there is a failure.](https://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.basevalidator(v=vs.110).aspx) Not everyone uses a summary (especially on simple pages), and your documentation (I just looked) makes no mention of either the Text or ErrorMessage property. I cannot be the only person to ever have this issue, and I am sure I will not be the last.
To me, the callout is for the validator and not the summary, and it is counterintuitive to use the message intended for the summary and not the validator itself.
At the very least, please update your [documentation page](http://ajaxcontroltoolkit.codeplex.com/wikipage?title=ValidatorCallout%20Control&referringTitle=Tutorials) for this control to mention which attribute it relies on.