I just updated to the latest Winforms release and now none of the Winforms will open in the designer. All have the same error message (attached in the screenshot as well).
Instances of this error (1)
1. Hide
Call Stack
at
System.ComponentModel.TypeDescriptor.AddAttributes(Object instance, Attribute[]
attributes)
at
Microsoft.VisualStudio.Design.VSDesignSurface.CreateDesigner(IComponent
component, Boolean rootDesigner)
at
System.ComponentModel.Design.DesignerHost.AddToContainerPostProcess(IComponent
component, String name, IContainer containerToAddTo)
at
System.ComponentModel.Design.DesignerHost.PerformAdd(IComponent component,
String name)
at
System.ComponentModel.Design.DesignerHost.System.ComponentModel.Design.IDesignerHost.CreateComponent(Type
componentType, String name)
at
System.ComponentModel.Design.Serialization.DesignerSerializationManager.CreateInstance(Type
type, ICollection arguments, String name, Boolean addToContainer)
at
System.ComponentModel.Design.Serialization.DesignerSerializationManager.System.ComponentModel.Design.Serialization.IDesignerSerializationManager.CreateInstance(Type
type, ICollection arguments, String name, Boolean addToContainer)
at
System.ComponentModel.Design.Serialization.TypeCodeDomSerializer.Deserialize(IDesignerSerializationManager
manager, CodeTypeDeclaration declaration)
at
System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager
manager)
at
Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager
serializationManager)
--- End of stack trace from previous location where
exception was thrown ---
at
Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager
serializationManager)
at
System.ComponentModel.Design.Serialization.BasicDesignerLoader.BeginLoad(IDesignerLoaderHost
host)
3 Answers, 1 is accepted
Rank 3
Bronze
Iron
Iron
I found this suggestion: https://www.telerik.com/forums/on-every-new-project-value-cannot-be-null-parameter-name-instance
Followed those instructions, but still have the same issue.
Rank 3
Bronze
Iron
Iron
Hi, Troy,
I am glad that the problem you were facing is now resolved.
Indeed, the most common problem after upgrading is that you can't open the designer because the project is referring to the old version. In such cases, you need to carefully check the references to all Telerik controls in your project and make sure that they are the same version considering the suffix as well (.20 or .40). Better yet, you can remove all references and add them anew by using the DLLs from your fresh installation. Delete the license.licx file. After that, you should rebuild your project, close Visual Studio and open it again to make sure that no references are kept in the memory by Visual Studio.
I hope this information helps. If you need any further assistance please don't hesitate to contact me.Regards,
Dess | Tech Support Engineer, Sr.
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