I am trying to view the code in mmMaintenanceForm, but when I open it I get the following message:

The designer could not be shown for this file because none of the classes within it can be designed. The designer inspected the following classes in the file: mmMaintenanceForm --- The base class 'OakLeaf.MM.Main.Windows.Forms.mmBusinessForm' could not be loaded. Ensure the assembly has been referenced and that all projects have been built.
Hide

at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.EnsureDocument(IDesignerSerializationManager manager)
at System.ComponentModel.Design.Serialization.CodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager manager)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.PerformLoad(IDesignerSerializationManager serializationManager)
at Microsoft.VisualStudio.Design.Serialization.CodeDom.VSCodeDomDesignerLoader.DeferredLoadHandler.Microsoft.VisualStudio.TextManager.Interop.IVsTextBufferDataEvents.OnLoadCompleted(Int32 fReload)


Is there some step that I am missing?