what is 401 http code example

Example: HttpErrorResponse {headers: HttpHeaders, status: 401, statusText: "Unauthorized"

//if you are getting this error and are using Firebase it could be that you 
 //need to set the rules of your Realtime database to true to allow your 
 //app access to your database:
 
 "rules": {
     ".read" : true ,
    ".write": true
     }