The following stack trace is only available:
<ErrorReport GeneratedDate="2015-10-07 14-10-25 435"><Exception><Type>ArgumentNullException</Type><Message>Value cannot be null. Parameter name: key</Message><Source>mscorlib</Source><TargetSite>Int32 FindEntry(TKey)</TargetSite><StackTrace> at System.Collections.Generic.Dictionary`2.FindEntry(TKey key) at Telerik.WinControls.RichTextBox.Proofing.WordDictionary.GetWordsByMetaphoneKey(String word) at Telerik.WinControls.RichTextBox.Proofing.DocumentSpellChecker.GetSuggestionsForDictionary(IWordDictionary dictionary, Dictionary`2 suggestions, String word) at Telerik.WinControls.RichTextBox.Proofing.DocumentSpellChecker.GetSuggestions(String word, CultureInfo culture) at Telerik.WinControls.UI.SpellCheckWordByWordForm.Initialize(String word, IControlSpellChecker spellCheckingManager) at Telerik.WinControls.UI.SpellCheckWordByWordForm.Telerik.WinControls.RichTextBox.UI.Extensibility.SpellChecking.ISpellCheckForm.Check(RadRichTextBox richTextBox, String word) at Manad.Plus.WindowsUI.Common.Controls.LocalInputBehaviour.ProcessRightMouseButtonDown(MouseEventArgs e) at Telerik.WinControls.RichTextBox.UI.InputBehavior.ProcessMouseDown(MouseEventArgs e) at Telerik.WinControls.RichTextBox.RadRichTextBox.OnMouseDown(MouseEventArgs e) at System.Windows.Forms.Control.WmMouseDown(Message&amp; m, MouseButtons button, Int32 clicks) at System.Windows.Forms.Control.WndProc(Message&amp; m) at Telerik.WinControls.RadControl.WndProc(Message&amp; m) at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)</StackTrace><Data>System.Collections.ListDictionaryInternal</Data><IsTerminating>False</IsTerminating><ExceptionInnerLevel>0</ExceptionInnerLevel>