To uninstall P6 Integration API from a WebSphere server:
Do one of the following:
On Windows platforms, from the Start menu, choose Programs, app name, Uninstall app name.
On Unix platforms, change to the installableApps/app name directory under the WebSphere install directory and run the uninstallws.sh script.
Launch the WebSphere Application Console.
Remove the current P6 Integration API deployment.
If you will use the same apihome directory for the new deployment, delete the existing WAR file from that directory to avoid conflict with the new PrimaveraAPI.war file.