When Outlook 2007 and 2010 subscribe to an internet calendar (via a webcal://
link to an iCalendar or vCalendar file), how often do they auto-update? Is there a way to configure this, either in the file downloaded or in Outlook preferences? I know the file can specify a minimum refresh interval (via the X-PUBLISHED-TTL
field), but I don't see a way to explicitly specify a recommended interval.
For Outlook 2013 if you hit send/receive that will sync the calendars as well. To adjust that interval go to File > Options > Advanced then scroll down to find Send/Receive. The options to adjust the intervals for auto Send/Receive are found there.