Non-existent, not used project reference causes error in WinForms VS designer

Today I was struck by another „self-explanatory” 😛 Visual Studio exception: The path is not of a legal form. Hide at System.IO.Path.NormalizePathFast(String path, Boolean fullCheck) at System.IO.Path.GetFullPathInternal(String path) at System.Reflection.AssemblyName.GetAssemblyName(String assemblyFile) at Microsoft.VisualStudio.Design.VSTypeResolutionService.AddProjectDependencies(Project project) at Microsoft.VisualStudio.Design.VSTypeResolutionService.AssemblyEntry.get_Assembly() at Microsoft.VisualStudio.Design.VSTypeResolutionService.AssemblyEntry.Search(String fullName, String typeName, Boolean ignoreTypeCase, Assembly& assembly, tring description) at Microsoft.VisualStudio.Design.VSTypeResolutionService.SearchProjectEntries(AssemblyName assemblyName, …

System.IndexOutOfRangeException: Index -1 does not have a value

I had encountered a strange error in my winforms .NET application, when I entered a form and clicked a GridView bound to a IList<T> collection: System.IndexOutOfRangeException: Index -1 does not have a value. at System.Windows.Forms.CurrencyManager.get_Item(Int32 index) at System.Windows.Forms.CurrencyManager.get_Current() at System.Windows.Forms.DataGridView.DataGridViewDataConnection.OnRowEnter(DataGridViewCellEventArgs e) at System.Windows.Forms.DataGridView.OnRowEnter(DataGridViewCell& dataGridViewCell, Int32 columnIndex, Int32 rowIndex, Boolean canCreateNewRow, …