MaskedEditExtender causes Application Error

[vsk9-cdc]

The AJAX Control Toolkit <VERSION 1.0.10301.0>

The installation method

• Installer

Minimal steps to reproduce the bug

Added the MaskedEditExtender code shown below to my page. The page will not render with this code in place. Page renders fine with text box only and without MaskedEditExtender

Using Visual Studio 2017, .NET 4.7.2, and VB.NET

Actual result

Application fails with Application Error

Expected result

Page renders

Browser(s) used

MS Edge

A site deployment method

• Installer

<asp:textbox id="Textbox1" runat="server" MaxLength="10" Width="110px" AutoComplete="off"></asp:textbox>

<ajaxToolkit:MaskedEditExtender ID="MaskedEditExtender1" runat="server"
TargetControlID="txt_StartDate"
Mask="99/99/9999"
MessageValidatorTip="false"
OnFocusCssClass="MaskedEditFocus"
OnInvalidCssClass="MaskedEditError"
MaskType="Date"
DisplayMoney="Left"
AcceptNegative="Left" />