Examinations for Google App Engine Java update permissions error

I have a gae application (created via GRAILS) which loaded up fine, though my first attempt is not working (due to me not testing locally first), but the point being that it loaded up fine.

Now when I try and do an update on windows:

"%APPENGINE_HOME%/bin/appcfg.cmd" update ./target/war

I get the message - You do not have permission to modify this app (a开发者_如何学JAVApp_id=u'MyProject'). I have set google.appengine.application="myproject" (remembering I was able to previously deploy a version). Note, my project in IDEA is MyProject in a directory of the same name.

Are there reasons other than wrong username and password (I can log into google application fine with the same details) to get this message? I am wondering if the case in the message V the app_id means it is not picking up the app_id properly ?

You need to create an app, then you are given an app ID. Every time you deploy the app you need the App ID, User Name, Password as well as a Version (which I always leave at 1)