React Native: Command `run-ios` unrecognized

Question

I have two different ReactNative-Projects:

• a) a project from januar 2016
• b) a complete new react-native project from now (march 20th 2016)

Answer 1

What caused this for me was running npm install --save axios when actually the system was previously using yarn instead of npm.

To solve this, instead of deleting the node_modules folder, which can lead to more problems, and if you prefer to run npm anyway or don't have a preference either way, the error should have instructed for you to run npm install. If you literally follow those instructions, you will be able to run: react-native run-ios afterwards.