need a msg popup in C#,asp.net

[hello12356789]

i m using the update panel.
i wan to displya the msg in the screen that the database id already exist.
i m trying

Response.Write( "<script>window .alert('Data with the Same id already exists');</script>");
but is in not working
is there any control in ajax to do it or which is the alrenative way to do this task

[nateraaaa]

The Response.Write statement looks correct. Have you used the debugger to verify that the Response.Write is being reached in your code path?

Nathan