Ensure that you have installed AutoREST globally. If not, perform the following to install AutoREST:
Install Node.js which will install npm.
Go to https://nodejs.org/en/download/, download the Node.js Installer and select the required version for your environment (Windows or Mac).
Using command prompt on Windows or Terminal on Mac, enter the following command to install AutoREST globally on your machine:
npm install -g autorest
You can verify the version of AutoREST and any installed extensions with the following command:
AutoREST --version
Notes:
It is preferred to install the latest version of AutoREST.
The CSharp extension must be available for use with developing an ePortal Xamarin App.