Использование EWS Java API:
ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010);
ExchangeCredentials credentials = new WebCredentials("USERNAME", "PASSWORD");
try {
service.setCredentials(credentials);
service.setUrl(new URI("URL"));
ItemId id = new ItemId("ITEM ID");
new Item(service);
Item item = Item.bind(service, id);
EmailMessage email = (EmailMessage) item;
if (ewsModel.getMarkEmailAsRead().booleanValue()) {
email.setIsRead(true);
email.update(ConflictResolutionMode.AlwaysOverwrite);
}}