Entering data in forms - intermittently crashes with error 'The RPC server is unavailable'

Symptom

The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.Runtime.InteropServices.COMException (0x800706BA): The RPC server is
unavailable.
at System.RuntimeType.InvokeDispMethod(String name, BindingFlags
invokeAttr, Object target, Object[] args, Boolean[] byrefModifiers, Int32
culture, String[] namedParameters)
at System.RuntimeType.InvokeMember(String name, BindingFlags invokeAttr,
Binder binder, Object target, Object[] args, ParameterModifier[] modifiers,
CultureInfo culture, String[] namedParameters)
at Microsoft.VisualBasic.CompilerServices.VBBinder.InvokeMember(String
name, BindingFlags invokeAttr, Type objType, IReflect objIReflect, Object
target, Object[] args, ParameterModifier[] modifiers, CultureInfo culture,
String[] namedParameters)
at
Microsoft.VisualBasic.CompilerServices.LateBinding.InternalLateCall(Object
o, Type objType, String name, Object[] args, String[] paramnames, Boolean[]
CopyBack, Boolean IgnoreReturn)
at Microsoft.VisualBasic.CompilerServices.LateBinding.LateCall(Object o,
Type objType, String name, Object[] args, String[] paramnames, Boolean[]
CopyBack)
at Cognos.Controller.Forms.ControllerMDI.DoAction(Int32 iMenuIDNumber,
ControllerMenuItem ClickedItem)
at Cognos.Controller.Forms.ControllerMDI.Menu_Click(Object sender,
EventArgs e)
at System.Windows.Forms.MenuItem.OnClick(EventArgs e)
at System.Windows.Forms.MenuItemData.Execute()
at System.Windows.Forms.Command.Invoke()
at System.Windows.Forms.Control.WmCommand(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg,
IntPtr wparam, IntPtr lparam)

************** Loaded Assemblies **************
mscorlib
Assembly Version: 1.0.5000.0
Win32 Version: 1.1.4322.2300
CodeBase: file:///c:/windows/microsoft.net/framework/v1.1.4322
/mscorlib.dll
----------------------------------------
CCR
Assembly Version: 8.1.662.0
Win32 Version: 8.1.662.0
CodeBase: file:///C:/Progra m%20Files/Cognos/ccr/CCR.exe
<........>