+ 0 Votes Some info NetMan1958 4 years ago We use iPhones with our exchange 2003 here. Use the web address i.e. if you access your OWA with "server.domain.com/exchange" enter "server.domain.com" in the iphone. We have a certificate signed by a commercial CSA and use SSL on. You might have an issue if you have a self-signed cert but I'm not sure. Also, I had to uncheck the "enable anonymous access" box int the properties for the exchange-oma in IIS.