Nearest Snap Problem

[tblack.62739]

I've got a computer that will not allow me to modify my Nearest Snap button. It keeps tossing up the error:

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

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
at Autodesk.AutoCAD.Customization.CustWrap.IsPopMenuEmpty(PopMenu pop, ArrayList empties, ArrayList nonEmpties)
at Autodesk.AutoCAD.Customization.CustWrap.IsPopMenuEmpty(PopMenu pop, ArrayList empties, ArrayList nonEmpties)
at Autodesk.AutoCAD.Customization.CustWrap.FindEmptyPopMenus()
at Autodesk.AutoCAD.Customization.CustWrap.FileValidation()
at Autodesk.AutoCAD.Customization.CustWrap.Save()
at Autodesk.AutoCAD.Customization.Document.Save()
at Autodesk.AutoCAD.Customization.MainForm.okButton_Click(Object sender, EventArgs e)
at Autodesk.AutoCAD.Customization.MainForm.applyButton_Click(Object sender, EventArgs e)
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.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)
...

Can anyone help me with this problem?