I had to redirect http to Https in Exchange 2013 OWA
Open IIS, Right Click – Explore
Take a Backup of web.config file
add the below content between –
</location>
Add Content in this space
</configuration>
And Paste it with –
<system.webServer>
<httpErrors>
<error statusCode="403" subStatusCode="4" path="https://mail.careexchange.in/owa" responseMode="Redirect" />
</httpErrors>
</system.webServer>
Now it should redirect all http to Https . Where the URL has been defined above