Synching iPhone with internet calendar (.ics) Looks like my issue has been around for a while (iOS 5.0.1 (iPhone 4s) unable to synchronize with Internet Calendar File (ics)) — has anyone come up with a fix yet?  I am trying to sync my iPhone calendars with the calendar on my PC that is in .ics format.  The .ics file is located on a home server that allows both me and my wife to see each other’s calendars and its been working great.  Now, I want to be able to see my calendar from my iPhone 4 (with OS 6.1) .. and I’ve tried setting it up with: Settings / Mail, Contacts, Calendars / Add Account… / Other / Add Subscribed Calendar. With every possible configuration I can think of, I get the same response: 


  Calendar Subscription — Unable to verify account information


For server name, I’ve tried actual servername, IP address, etc; we do have security on the server but I put in the account name and password … ‘nuthin! Unable to verify. Through the phone's browser, I am able to open up the folder on our server and see the .ics file. The path is 


  xxxx.homeserver.com/webcal/nat_calendar.ics. 


I've tried sending an invite to myself, opening it in the phone, clicking on the link and I get this error: 


  Cannot Subscribe: Could not subscribe to the calendar nat_calendar.ics from myservername. 


Seems simple. What am I missing here?
Any ideas?
I found the answer to my particular issue.  The reason that my iPhone could not subscribe to a published Outlook .ics calendar was because the MIME type of the .ics file was wrong.  As recommended in this brilliant post by Joe Bradford, I went into IIS, changed the MIME type from application/octet-stream to text/calendar, and iPhone could connect and subscribe without further issue. Success! 

PS: I did not run into the second issue that Joe chased down, which was having to remove the Byte Order Mark (BOM) from the .ics file via a hexadecimal editor.