Final Cut Pro X export Error 27

I'm currently trying to export a final cut project... its 1 hour and 54 minutes in length and keeps returning an 'Error 27' message during export.

I've tried multiple codecs with the same issue.

I've tried to narrow down where the error is occuring within the timeline by exporting sections at a time, but all sections seem to be exporting fine...

Can't seem to find a list of error codes and their meanings, but there doesnt seem to be anything avaialble...

Any suggestions to get it to export properley?

Thanks.