whenever i click form10 then this error come.

Warning 1   Value cannot be null.
Parameter name: objectType      0   0   

Instances of this error (1)  

1.   Hide Call Stack 

at System.ComponentModel.TypeDescriptor.TypeDescriptionNode.GetRuntimeType(Type objectType)
at System.ComponentModel.TypeDescriptionProvider.GetRuntimeType(Type reflectionType)
at Microsoft.VisualStudio.Design.MultiTargetingContextProvider.GetRuntimeType(Type objectType)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.HandlesClauseManager.GetFieldType(String fieldName, Type documentBaseType)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.HandlesClauseManager.GetReferencedComponentType(String componentName, CodeTypeDeclaration codeTypeDecl, ITypeResolutionService loader, IDictionary& cache)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.HandlesClauseManager.ParseHandlesClauses(CodeTypeDeclaration codeTypeDecl, Boolean updateCache)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomParser.OnMethodPopulateStatements(Object sender, EventArgs e)
at System.CodeDom.CodeMemberMethod.get_Statements()
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)
at System.ComponentModel.Design.Serialization.BasicDesignerLoader.BeginLoad(IDesignerLoaderHost host)  

and form name is showing like

form_load_1 ...with all codes it adding _1

please help me


I am assuming this is a design time error and not a run time error judging by my quick bit of research on Google. I am sure there are a number of reasons why this might be caused so it is difficult to offer a solution just based on the stack trace that you have provided (although there may be others that understand it better than I do).

Looking at some of the details from various sources, some suggest to do a clean of your project (Build > Clean Solution) while others suggest to copy all of the code for the form (including the designer generated code), delete the form and create a new form and paste all of the code back, although this sounds a bit hacky to me but may work.

Did you mess around at all with any of the code in Form10.designer.vb? This can cause issues. Did you rename any controls and potentially have mismatched event handlers?

If you can provide more information on what occurred prior to you receiving this error it would be helpful.

im trying to solve it.. will update

These type of error could be shown if you try to paste codes in the Form Class copying from other form class without designing first.