Hi, I got the problem to showing error message using custom validator,
this is my Source
ASP.net
<dx:ASPxCallback ID="ASPxCallback1" runat="server" ClientInstanceName="Callback">
<ClientSideEvents CallbackComplete="function(s, e) { LoadingPanel.Hide(); }" />
</dx:ASPxCallback>
<div>
<asp:ScriptManager ID="MyManager" runat="server">
</asp:ScriptManager>
</div>
<dx:ASPxLoadingPanel ID="LoadingPanel" runat="server" ClientInstanceName="LoadingPanel"
CssFilePath="~/App_Themes/DevEx/{0}/styles.css" CssPostfix="DevEx" ImageSpacing="5px"
Modal="True">
<Image Url="~/App_Themes/DevEx/Web/Loading.gif" Width="50px">
</Image>
<LoadingDivStyle BackC ...
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