Performing a Force undeploy on a Running Version of an Application
When you upgrade an application to a new version and deploy it, the deployment may either succeed or fail. If you want to Force undeploy a successfully deployed application that is in a Running state you must be careful. Closely evaluate your needs before you perform a Force undeploy on a Running version of an application.
Force undeploying a version that is in a Running state removes the current version and its associated data, but leaves the older versions in their prior state (typically Preparing for Undeploy, which means that the undeployment of a previous version is waiting for process instances to be completed).
If your application is Preparing for Undeploy, it will no longer allow the creation of new process instances, but will keep waiting for existing ones to complete. If you want the system to allow new process instances in this situation, you must deploy another new version to get the application to the Running state. Be aware that a version that is in a Preparing for Undeploy state cannot be transitioned to a Running state. See the topic How to Identify a Failed Upgrade/Deployment for more details about how to identify a failed deployment.