GREP does not work
//*******************************************
//CODE
//*******************************************
InDesign.Application InDesignApp = (InDesign.Application)Activator.CreateInstance(Type.GetTypeFromProgID("InDesign.Applicati on"));
InDesignApp.Activate();
//Create Document
InDesign.Document InDesignDoc = InDesignApp.Documents.Add();
//PageWidth
InDesignDoc.DocumentPreferences.PageWidth = Convert.ToDouble(numericUpDown_width.Value);
//PageHeight
InDesignDoc.DocumentPreferences.PageHeight = Convert.ToDouble(numericUpDown_height.Value);
InDesignDoc.DocumentPreferences.PageOrientation = idPageOrientation.idPortrait;
InDesignDoc.DocumentPreferences.PagesPerDocument = 50;
InDesignDoc.DocumentPreferences.StartPageNumber = 1;
InDesign.Page page = (InDesign.Page)InDesignDoc.Pages[1];
InDesign.Layer layer = (InDesign.Layer)InDesignDoc.Layers[1];
//Place *.docx in Document
page.Place("C:\\sample.docx", new[] { 0, 0 }, layer, false, true);
InDesign.Document Doc = (InDesign.Document)InDesignApp.ActiveDocument;
//Clear the find/change grep preferences
InDesignApp.FindGrepPreferences = idNothingEnum.idNothing;
InDesignApp.ChangeGrepPreferences = idNothingEnum.idNothing;
//Set the find options
InDesignApp.FindChangeGrepOptions.includeFootnotes = true;
InDesignApp.FindChangeGrepOptions.includeHiddenLayers = true;
InDesignApp.FindChangeGrepOptions.includeLockedLayersForFind = true; ;
InDesignApp.FindChangeGrepOptions.includeLockedStoriesForFind = true;
InDesignApp.FindChangeGrepOptions.includeMasterPages = true;
//Regular expression for finding an email address
InDesignApp.FindGrepPreferences.findWhat = "(?i)[A-Z]*?@[A-Z]*?[.]...";
Doc.FindGrep();
//Apply the change to 24-point text only
InDesignApp.FindGrepPreferences.pointSize = 28;
InDesignApp.ChangeGrepPreferences.underline = true;
Doc.ChangeGrep();
//Clear the find/change grep preferences
InDesignApp.FindGrepPreferences = idNothingEnum.idNothing;
InDesignApp.ChangeGrepPreferences = idNothingEnum.idNothing;
//*******************************************
//END CODE
//*******************************************
where am I wrong?