I published a lot services for geoprocessing. Most of them are the long running services. Those services manipulate data but user do not wait for the results. When I use REST Submit Job in the web browser sometimes it works without errors, but more often my processes are cancelled. In the web browser I get esriJobMessageTypeInformative that the service was canceled and aborted by User. This is very annoying behavior because I can not find the reason of this state. Another strange thing is a time of canceling. There is no rule when the process is aborted, sometimes after 4 hours, sometimes after 45 min. This is not the problem with pooling because I have never reached any of maximum times. Any help or idea how to solve it would be appreciated.