Currently we are working on programmatically updating constants and restarting our Mendix applications. The issue we have is that both setting constants and restarting works, but only for our Test and Acceptance environments. Without clear feedback or reason it doesn’t seem to work for our Production environment. We verified that the API user account has Production API rights in the Sprinter. Also we tried before restarting Production to authenticate the user in the Sprinter using the Google Authenticator. Our HTTP requests below are authenticated using a header API key and username, not visible here. When we focus for now on restarting one of our production apps using the Mendix Deploy API (see also https://docs.mendix.com/apidocs/deploy-api), we first use a Post Request to start the application. Then we use a GET Request to see whether the application already started. Here we obtain different results for our app in the Production and Acceptance environment. The HTTP requests and responses we obtain for our app in Production using Postman are as follows: HTTP POST: https://deploy.mendix.com/api/1/apps/coreql/environments/production/start/ RESPONSE: { "JobId": "680038be-6b97-46fb-8def-2d1cce0ae20d" } HTTP GET: https://deploy.mendix.com/api/1/apps/coreql/environments/production/start/680038be-6b97-46fb-8def-2d1cce0ae20d RESPONSE: { "errorMessage": "Cannot start app: AppContainerStartFailed (VICTOIRE)", "errorCode": "START_FAILED" } Could this be an authentication issue or something else? Doing exactly the same exercise for our app in the Acceptance environment gives the following results: HTTP POST: https://deploy.mendix.com/api/1/apps/coreql/environments/acceptance/start/ RESPONSE: { "JobId": "3041eb98-a920-474d-bcbc-b9ad78c5d712" } HTTP GET: https://deploy.mendix.com/api/1/apps/coreql/environments/production/start/3041eb98-a920-474d-bcbc-b9ad78c5d712 RESPONSE: { "Status": "Starting" } After a couple of seconds the application has indeed started! Maybe anyone can try this little exercise with their own application using the Chrome plugin Postman and comment on the results they get below. Thank you in advance if you are willing to check this out! I hope anyone can give us a clue why the Mendix Deploy API does not start our production application. Kind regards, Jeroen Moonen