IONIC : A utility CLI has unexpectedly closed

Run the below command, being in root directory of Ionic project:

npm install @ionic/app-scripts@latest --save-dev

Then you can try Ionic serve or Ionic s.

I had a similar issue. I tried several different solutions, and for some reason different ones worked on different machines. Because I'm an illogical masochist, I attempted to fix this issue in the same project on 3 different laptops instead of sending the new fixed version to the other laptops.

The best answer I came up with is to:

• Delete node_modules
• copy node_modules from a different project (I used an earlier version of my app)
• run npm i to install any missing modules

I think this approach should work for almost all instances.

I had a similar issue:

Assertion `args[1]->IsString()' failed.

A utility CLI has unexpectedly closed

I fixed that by installing natives lib through npm:

npm i natives

Simpy run

npm install @ionic/app-scripts@latest --save-dev

and then

ionic serve

This error is because of some audit during installing a plugin or adding a plug in