Syncronize Calendar between Outlook and iPhone

Login to webmail
Go to calendar,  click on calendar icon on left
Under Actions, click add to outlook
Choose your Outlook version
Name Calendar so you know what it is, click ok
On Launch Application page click on Microsoft Outlook and click ok
Click Yes
Now is Outlook under Calendar you will see a SharePoint calendar named SmarterMail – Whatever you named it. Make sure to put all appointments to the SharePoint calendar in outlook not the default calendar.  So you can see them on your phone. 
 
Next you must setup the CalDAV client on your iPhone:
 
CalDAV for iCal
Follow these steps to set up sync through CalDAV:
 
    Settings
    Mail, Contacts, Calendar
    Add Accounts
    Other
    Under Calendars select Add CalDav Account
    Sever: webmail.domainname.com;
    User Name: your whole email address
    Password
    Description: whatever friendly name you want to use
    Next
    If it  say Cannot Connect Using SSL. DO you want to try setting up with account without SSL?
    Click Continue
    Will say account verification failed, click ok
    Will say fail click save
    It will take you to the account screen click on the account and then click advanced settings
    Use SSL set to OFF
    Port: 80
    Account Url = domain name /webdav/

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