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I would appreciate if you guys setup a simple sample project for me that uses Syncfusion Tools controls. Most importantly the ButtonAdv and perhaps Waiting Pop-up.

In my project I target 4.5 .NET Framework and have a GridGroupingControl that works fine. I followed all examples and yet although the project builds, I get an error as soon as I get to the page containing the button.

The error message is quoted at the bottom of this post.

Another one is Waiting Pop-up. Although when I incorporate it in my project and it compiles an runs -- I never get to see the pop-up in action. No error's either.

Could you please help me out by setting a sample project.




Server Error in '/' Application.

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>). 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.Web.HttpException: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).

1 Reply

GA Gurunathan A Syncfusion Team April 23, 2014 07:35 AM UTC

Hi Alex,

Thanks for contact syncfusion support.


We suspect that, the reported issue may be caused by syntax error from button control. So we have prepared a simple sample to show case the behaviour of both button and waiting popup.


The documentation for the button control in ASP.NET is available in following link:



The documentation for the waiting popup control in ASP.NET is available in following link:



Please find the online sample demo link in below :

Button : https://asp.syncfusion.com/demos/ui/tools/Button/CoreFeatures/cs/CoreFeatures.aspx

Waiting popup : https://asp.syncfusion.com/demos/ui/tools/WaitingPopup/CoreFeature/cs/CoreFeature.aspx


Please find the attached sample in below:

Please let us know if you have further concern.




Attachment: wp_F116190_5a19f6d3.zip

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