After you have subscribed to an Internet calendar, you can change the location of the Internet calendar, the update frequency, and force an update.
In the Folder List, right-click the subscribed calendar, and then click Subscribe.
(Optional) In the Location field, type the new URL for the Internet calendar.
(Optional) In the Update Frequency drop-down list, select the update frequency.
(Optional) Click Refresh to force the Internet calendar to reload.
Click OK.