I am running OS X 10.12.5 (Sierra). I updated to the latest version of R to no avail.
2017-07-09 17:32:06.020 R[6374:3009215] *** RController: caught ObjC exception while processing system events. Update to the latest GUI version and consider reporting this properly (see FAQ) if it persists and is not known.
*** reason: *** -[__NSArrayM objectAtIndex:]: index 18446744073709551615 beyond bounds [0 .. 157]
*** name: NSRangeException, info: (null)
*** Version: R 3.4.1 (72865) R.app R 3.4.1 GUI 1.70 El Capitan build
Consider saving your work soon in case this develops into a problem.