One of the problems with using Expo development when the React native

When I was in the use of Expo development project, the first execution NPM run ios will be submitted to the errors, and then execute once is normal.

Excuse me, what's the solution?

As shown in figure：

Error screenshot

Error is as follows: › npm run ios

react-native-starterkit@0.1.0 ios /Users/****/work/react-native-starterkit

react-native-scripts ios

10:09:56: Starting packager...

10:10:09: Starting simulator...

10:10:30: Failed to start simulator:

Error: Process exited with non-zero code: 60

Exiting...

via 祝梓毅