Moving this question to the Exchange Development thread per Jon-Alfred's suggestion (http://social.technet.microsoft.com/Forums/en/exchangesvrdevelopment/thread/e297b09d-0a69-4a62-8da1-12084df9265f) Hi folks, I have Exchange 2007 code that uses FindItem to search the calendar folder by the category field. When ported to Exchange 2010 Sp1, findItem throws the error: "ErrorContainsFilterWrongType: The Contains filter can only be used for string properties." I realize that categories are now a multi-value field, but I haven't been able to get findItem to work. Could someone help me construct a search expression for EWS Managed API or XML. Here are samples of the XML (single category), or Managed API (in VB) for multiple categories. Thanks, Russ

You might get a faster answer if you post your question here: Development (Topics discussed include: Web services, APIs, application conversion and apps in general) http://social.technet.microsoft.com/Forums/en/exchangesvrdevelopment/threads MCTS: Messaging | MCSE: S+M