Hello gjorveno,

Most probably you could do something like the following before the Dialog is opened:

private void ultraSpellChecker1_SpellCheckDialogOpening(object sender, Infragistics.Win.UltraWinSpellChecker.SpellCheckDialogOpeningEventArgs e)

{

 e.SpellCheckDialog.Font = new Font("Tahoma",19f, FontStyle.Bold);

}

Please feel free to let me know if there is anything else that I could help you with.