How to get second modalPopupExtender to open?

[engmgm]

I have a web page with two modalpopupextenders on the same page, both of them being called from the codebehind using .show()However, only the first such panel ever opens, and stepping through the code reveals that the second panel's show() is called, but then nothing happens on the page itself. All the proper controls are present such as the targetcontrolid and popupcontrolid. I've pasted the two extender controls below, the first being the one that works with no issue.\[code\]<cc1:ModalPopupExtender TargetControlID="lbHidden1" ID="pnlEditNickname_ModalPopupExtender" BehaviorID="pnlEditNickname_ModalPopupExtender" runat="server" DynamicServicePath="" Enabled="True" BackgroundCssClass="modalBackground" PopupControlID="pnlEditNickname_Modal" DropShadow="false" CancelControlID="btnModalEditCancel"> </cc1:ModalPopupExtender><cc1:ModalPopupExtender TargetControlID="hiddenLB2" ID="pnlCancelCert_ModalPopupExtender" BehaviorID="pnlCancelCert_ModalPopupExtender" runat="server" DynamicServicePath="" Enabled="True" BackgroundCssClass="modalBackground" PopupControlID="pnlCancelCertModal" CancelControlID="btnCancelCertDelete" DropShadow="false"> </cc1:ModalPopupExtender>\[/code\]