#6 Deleting admin uncaught exception

[Ben]

If I try to delete admin the program crashes and I get this error:
Exceptions.InputException was unhandled
Message="Error: You may not remove the last administrator. Promote another user to administrator status first, otherwise nobody will be able to manage users."
Source="WITS Client Application"
StackTrace:
at Data_Manipulation_Logic_Module.DataTranslationLayer.checkForOtherAdministrators(User changedUser) in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\Data Manipulation Logic Module\DataTranslationLayer.cs:line 548
at Data_Manipulation_Logic_Module.DataTranslationLayer.deleteUser(String username) in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\Data Manipulation Logic Module\DataTranslationLayer.cs:line 160
at Data_Manipulation_Logic_Module.GUIAdapter.deleteUser(String username) in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\Data Manipulation Logic Module\GUIAdapter.cs:line 106
at GUI.Management.userGrid_CellContentClick(Object sender, DataGridViewCellEventArgs e) in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\GUI Module\Management.cs:line 297
at System.Windows.Forms.DataGridView.OnCellContentClick(DataGridViewCellEventArgs e)
at System.Windows.Forms.DataGridView.OnCommonCellContentClick(Int32 columnIndex, Int32 rowIndex, Boolean doubleClick)
at System.Windows.Forms.DataGridViewCell.OnMouseUpInternal(DataGridViewCellMouseEventArgs e)
at System.Windows.Forms.DataGridView.OnCellMouseUp(DataGridViewCellMouseEventArgs e)
at System.Windows.Forms.DataGridView.OnMouseUp(MouseEventArgs e)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.DataGridView.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Form.ShowDialog(IWin32Window owner)
at System.Windows.Forms.Form.ShowDialog()
at GUI.MainScreen.managementBtn_Click(Object sender, EventArgs e) in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\GUI Module\MainScreen.cs:line 239
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at GUI.Program.Main() in C:\Documents and Settings\Ben\Desktop\WITS\wits_client\WITS Client Application\GUI Module\Program.cs:line 21
at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()