Error in design form

Please how repair this error

en Microsoft.Win32.RegistryKey.Win32Error(Int32 errorCode, String str)
en Microsoft.Win32.RegistryKey.GetValueNames()
en Microsoft.VisualStudio.Shell.Design.WindowPaneProviderService.AppendWindowPanes(RegistryKey parentKey, ArrayList windowPanes)
en Microsoft.VisualStudio.Shell.Design.WindowPaneProviderService.GetRegisteredPanes(String extension)
en Microsoft.VisualStudio.Shell.Design.WindowPaneProviderService.CreateWindowPane(DesignSurface surface)
en Microsoft.VisualStudio.Design.Serialization.CodeDom.DeferrableWindowPaneProviderService.CreateWindowPane(DesignSurface surface)
en Microsoft.VisualStudio.Design.Serialization.CodeDom.DeferrableWindowPaneProviderService.DeferredWindowPane.EnsurePane()

Thanks

[787 byte] By [Oacampos] at [2008-1-4]