Issue: User tries to go into the OWA and change the options, but got a message saying “403 Sorry! Access denied” You don’t have permissions to open this page. Wait 15 minutes and try again. Customer already has the correct default role assignment policy assigned.
Cause: Troubleshooting revealed that ecpenabled was set to false for this user under casmailbox
Resolution: From PowerShell command prompt, type Set-casmailbox -id testuser -ecpenabled $true