Hi

I have a container aspx page which uses PageView to display 3 controls on seperate pages.  One of the controls is a datagrid which das buttons on the side to view a record in a separate aspx page & Control.  When I click on the button I get the error below.  I have tried putting this code in the web.config and also the page but I still get the error:

<%@ Page EnableEventValidation="true" %>

<pages enableEventValidation="true"/>

Server Error in '/MyositisPresentation' Application.
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Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Page EnableEventValidation="true" %> in a page.  For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them.  If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Page EnableEventValidation="true" %> in a page.  For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them.  If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. 

Stack Trace:

[ArgumentException: Invalid postback or callback argument.  Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Page EnableEventValidation="true" %> in a page.  For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them.  If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.]
   System.Web.UI.ClientScriptManager.ValidateEvent(String uniqueId, String argument) +368
   System.Web.UI.Control.ValidateEvent(String uniqueID, String eventArgument) +84
   System.Web.UI.WebControls.ImageButton.RaisePostBackEvent(String eventArgument) +51
   System.Web.UI.WebControls.ImageButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +31
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +32
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +72
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3840

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Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET Version:2.0.50727.42

Hi

Please try to install framework 2.0 SP2 bundled with framewrok 3.5 SP1. For more details pleae visit the following link

http://forums.asp.net/t/1354122.aspx

 Hai

 can you change Enableventvalidation="False" let me know 

 else check in your code behing , Have you used

if Not Ispostback  then

..////

End if

If not add this ..