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Syncfusion Feedback

How to resolve exception with Failed to create component while adding the components from toolbox to designer form?

Platform: WinForms |
Control: General
Tags: exception


This issue can be occurred when the Syncfusion controls in toolbox version is different from the GAC assemblies installed version in the machine. At that moment, it will throw the exception as “There is already a reference to the Syncfusion.Tools.Windows component in the project.  

If the GAC assemblies were not properly configured or previous version of Syncfusion assemblies were not removed properly from the machine, the issue can be occurred.


This problem can be resolved by installing the GAC assemblies properly. To install the GAC assemblies, please refer the below UG document,


To ensure whether the Syncfusion controls are configured properly for the .NET Framework version, please follow the below steps,

Step 1 

  • Close your application and clear all bin/obj files. 
  • Open Essential Studio and then Select Assembly Manager from Utilities Section to open Assembly Manager. 

Showing assembly manager section  



Step 2 

  • Remove all the installed versions from your machine by selecting Remove all versions and click on Perform Action button. 


Showing remove all assemblies version from GAC  



Step 3 

  • Install the current version by selecting the version and click on Perform Action button install the current version. 


Showing install the assemblies version to GAC  


Step 4 

  • Refer to the below link for tool box configuration with current version



Step 5 

  • Add the Syncfusion controls in designer and ensure the installed assemblies are referred properly in your application.

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