Hi, Earlier I upgraded to Mathematica 11.3. Yesterday I upgraded the os to OS X 10.13.5. When I try to run Benchmark.nb the `BenchmarkReport[]` never finishes. Same result after a fresh reboot of the machine and running only Mathematica. Any good idea why? Thanks ahead, János P.S. I am afraid to try my own programs. Attachments:

You were right. Somehow, during the OS X 10.13.5 update, things did go wrong. To fix it I installed the OS X 10.13.5 combo, then I trashed Mathematica, and reinstalled it from the dmg. Now Benchmark.nb is running. Thanks a lot.

The other "funny" thing is that when I pull from the menu "Parallel Kernel Configuration", it shows the master kernel with name "None". When I change it to "Local", it jumps back to "none" immediately and falls into an endless loop, by flipping between "Reformatting Notebook" and "Kernel is not responding to dynamic evaluation. You may either choose to abort and restart the kernel or continue waiting. Dynamic updating can be re-enabled using the Dynamic Updating Enabled command in the Evaluation menu." <Abort> <Continue Waiting>

Sorry to hear about your problem. I tested the benchmark on my other computer, a 15 inch MacBook Pro (2016), also running Mathematica 11.3 and 10.3.5, with no issues at all. When I first saw this, I thought that you had installed the macOS 10.4 beta. I installed this on another computer, but I don't have a third license for Mathematica, so I haven't checked it out yet.

OSX 10.13.5, Mathematica 11.3 does not creates BenchmarkReports?