I would start looking at why you can’t start the job using STRTCPSVR. If you can’t start the job this way, you’re not likely to be able to start it via navigator.
Try changing the logging on your job using CHGJOB LOG(4 00 *SECLVL) LOGCLPGM(*YES), then try the STRTCPSVR again. Then take a look in your joblog to see what messages you receive. There is most likely an error message which gives more insight into why the STRTCPSVR fails.
David Vasta –> One other thing to do and this works some of the time, Change the QSECOFR password, you can even make it the same things as it was before but for some reason that works some of the time. Just type over it and hit enter then try to start it back up and see if that helps. I had a server once that about once a month would do this and I used my little trick every time and it worked.