When we use the AJAX Control Toolkit ModalPopupExtender, sometimes we may get below error Sys.Extended is undefined$create(Sys.Extended.UI.ModalPopupBehavior, {"BackgroundCssClass":... After few hours of investigation, I realized that keyword I’m using it for scriptmanager.If you are using .net 4.0 framework, then change it from <asp:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"></asp:ToolkitScriptManager> To <asp:scriptmanager  ID="ToolkitScriptManager1" runat="server"></asp:scriptmanager > And vice-versa for 3.5 and below version.

Some time back, I was struggling to include the custom control to a page which I have created under the app_code folder to aspx page. Manually, I have done this with tags and so on. But I couldn't register it to the page. I felt I stuck here and there is no option to do that so. But I have noticed that many places of sample application, They referred the simple custom control in their pages. Below is that simple option to refer the custom controls to your asp.net pages.1.      Go to the aspx page design mode.2.      Register your control with the below template<%@ Register Assembly="__code" TagPrefix="[TagPrefix]" Namespace="Your.Namespace" %>3.      And use the control with the below syntax<[TagPrefix]: [TagPrefix] id=”” runat=server></<[TagPrefix]>Now you can easily compile and referrer the custom control under app_code folder.

Normally, We can easily convert text into image thru .net system.drawing namespace and their methods. but converting the HTML to Image in asp.net is bit a tricky one. Why it is so tricky? Good question. right? Trickiness is lying in-terms of output. The outcome of the image exactly should matches whatever you see that in your browser. I.e. WYSIWYG. [More]

While sending mails using system.net from asp.net, mail inbox always shows as username@domainname.com. This may not looks good and also not user-friendly to the users. [More]