Hello, I posted this in the message group also. I have developed a message store and every thing works fine. But occasionally when Outlook is synchronizing our message store becomes buggy. One example is that if our store is running in an exchange environment and Outlook is downloading an extremely large file requests will stack up in the details window. Once in a rare occasion Outlook will lock up during synchronization. Is there a way to detect synchronization and place our store in a dormant state while synchronization is happening? Any suggestions would be greatly appreciated. Thanks, Tom -