Sys.WebForms.PageRequestManagerTimeoutException: The server request timed out

The server request timed out

"Sys.WebForms.PageRequestManagerTimeoutException: The server request timed out"

Getting  "Sys.WebForms.PageRequestManagerTimeoutException: The server request timed out"

,when using a updatepanel. Why is that?

<add verb="GET" path="ScriptResource.axd" type="Microsoft.Web.Handlers.ScriptResourceHandler" validate="false"/>

 Possible Causes to this error are-

• The export operation was relatively long (something like 2 minutes)
• Ajax Extension Callback framework had a timeout.
• Do you have a particularly long running process on the server? Sounds like the PageRequestManager was waiting for a response and it didn't come back
• Probably you are running a server-side C# code and a client-side-script by a control like a Button all together.
• Or maybe you have written a client-side-script for a control which is placed in an updatePanel.

Possible Solutions to this error are-

• Try this in ur webconfig file.

                   <httpRuntime maxRequestLength="1024000" executionTimeout="999999"/>

• Try to solved it using three line of code in asp.net

                    1) <asp:ScriptManager ID="ScriptManager1" runat="server" AsyncPostBackTimeout ="360000"></asp:ScriptManager>       

                    2)<httpRuntime executionTimeout="360000"/>

• If you are running a server-side C# code and a client-side-script by a control like a Button all together.Or maybe you have written a client-side-script for a control which is placed in an updatePanel.

                 So Avoid them;

• Maximize the timeout to 10 hours

                  <asp:ScriptManager ID="ScriptManager1" AsyncPostBackTimeOut="36000" runat="server" />