private void AccessContacts(string findLastName) { var app = new Microsoft.Office.Interop.Outlook.Application(); Outlook.MAPIFolder folderContacts = app.ActiveExplorer().Session. GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts); Outlook.Items searchFolder = folderContacts.Items; int counter = 0; foreach (Outlook.ContactItem foundContact in searchFolder) { if (foundContact.LastName.Contains(findLastName)) { foundContact.Display(false); MessageBox.Show(foundContact.HomeTelephoneNumber.ToString()); counter = counter + 1; } } MessageBox.Show("You have " + counter + " contacts with last names that contain " + findLastName + "."); } }