This is using MS Exchange 2010 server on MS Windows 2008 R2 server. This server has been used for couple of years. Recently, users complaints that they can't access OWA for their web mails. I checked and found that the service - MS Exchange form-based authentication was found stopped. OWA operation resumes after restarted the mentioned service. But the problem is, this service looks like always stopped once per 2 week, why? How to stop this problem happens again?