SEL2990 Natural initialization Failed

I am a Natural Newbie, and I have a new user (for whom I have added member security thru ONLI in CICS on z/OS environment). User is receiving “SEL2990 Natural initialization Failed” which I would like to diagnose. Can I enable a trace, and will this allow me to diagnose what is wrong with this user’s Natural Security entry?

what is “ONLI”? That sounds like a CICS transaction, but it isn’t clear what that takes you to - does it take you to Natural and Natural Security?

“SEL2990” does not seem to be a standard Natural product error message (“SEL” is not a Natural message prefix that I can find). It is possible you have a CICS front-end program that is not working properly or is applying some other security.

Are other users able to connect to Natural using the same CICS transaction? What version of Natural are you using?