You are unable to edit Jobs even when write permission is provided for the project in TAC. You may see the following error:
org.talend.commons.exception.PersistenceException: Unable to access to url : http://hostname:8080/org.talend.administrator
Applies if you are behind a proxy and the Studio settings are not configured properly.
In Studio, navigate to Window > Preferences > Network Connections and set Active Provider to Direct.