Question: When I try to get the identifier of an EKEvent, all I get is a nil value. Since in iOS5 EKEvent is a subclass of EKCalendarItem, I figured I might be able to get the EKCalendarItem's UUID, but that returns nil as well. 

Every now and then I also get this error while trying to access the identifier or UUID property: 

```
CADObjectGetInlineStringProperty failed fetching uniqueID for EKPersistentEvent with error Error Domain=NSMachErrorDomain Code=268435459 "The operation couldn’t be completed. (Mach error 268435459 - (ipc/send) invalid destination port)"

```

I've been stuck on this problem for quite some time now, but figured it would be iOS5 beta related. But since we're now at iOS5, it's still not working.

Answer: 
> 
> When I try to get the identifier of an EKEvent, all I get is a nil value
> 
> 
> 

Try to save AND commit your event before retrieving the identifier :

```
[eventStore saveEvent:event span:EKSpanThisEvent commit:YES error:&err];
NSString *strId = [[NSString alloc] initWithFormat:@"%@", event.eventIdentifier];

```
eventIdentifier is set when the event is added to the EKEventStore. If you try to access this value before adding it, it would return null.