Originally Posted by gazhayes
After doing some research it seems to me that MacOS changed something in iCal which broke OmniFocus.
Perhaps in the next update they will fix it.
In the mean time, you may have to use this: http://gcaldaemon.sourceforge.net/index.html
I am still trying to get it to work. There must be a way to fix this, how can people use GTD without a calender...
What changed was that the MobileMe calendars changed from local+synched to server-based calendars (which are much more robust). If you elected to upgrade MobileMe a couple months back, that is. OmniFocus doesn't currently support server-based calendars. And I don't expect Apple will "fix" this, as it was an intentional change to something that's more reliable and better in many ways.
I use a calendar, but I don't use it in conjunction with OmniFocus. My calendar events are separate from my tasks, and it works OK for me because I don't live by way of artificial due dates. For 90% of my tasks, I do them when I can, which is around my calendar events.