Image is not getting displayed in Asp.Net

I am doing design work in asp.net and I tried to design my web form by adding image to "Image Url".

Here is my code

<asp:Image ID="Image3" runat="server" ImageUrl="~/curta.png" />

I am sure this is the usual way of adding images to the web form. I have tried using this image in all the other web forms. It is getting displayed, but not getting displayed in this web form. Its really weird for me.!! I tried using many images but nothing is getting displayed in this web form alone and I have also tried adding the images in "Images" folder and directed the url to that position. Still it didn't work..!!

I don't know what is wrong. Sorry if the question seems to be a silly one.!!Please help. Thanks in advance.