I get this message when I open iCal... "Calendar Cache" could not be moved because you do not have appropriate access privileges for "Calendars". I found the calendars folder in my user library folder. permissions are set to read & write and was applied to all enclosed items. My calendar works fine on my iPod touch.
i got same message after upgrading to snow leopard all i did was remove the icon from the dock drag the icon back to the dock from apps folder presto no probs accessing ical from doc that is, of course, if you tried to access from the doc and got this message hope this helps s2 in hong kong