Hai,

    I am developing a sample calendar application. Everything is working fine but sometimes organizer is mismatched. I am developing this by using ews manged api with version 2007_sp1.  

I am getting this problem after my mailbox is updated to exchanged 2013.

Any help is appreciated.

Thank you.

You need to more specific around the problem your having and provide a code sample  the forum guide https://social.technet.microsoft.com/Forums/office/en-US/77c07b69-eea6-43ab-9225-4b384cecfc9d/exchange-development-forum-guide-read-before-posting?forum=exchangesvrdevelopment goes though how and what you should provide.

As a stater if you using Exchange 2013 make sure you are using the latest version of the Exchange Managed API http://www.microsoft.com/en-au/download/details.aspx?id=42951 and set the Schema version to 2013.

Cheers
Glen