OT - Fax Serve

Sorry this is off topic, but I may go crazy. I haven't added a new user to
my Fax Serve in a while (ver 5).
So now when I want to, I can't add a new user.
I can delete users. I can change properties. Everyone is working, but I
can't add a new user.
I have stopped the services, I have rebooted the server. I have looked and
looked at the permissions, but I'm not seeing anything out of order and I
can't think of anything that has changed.
Any Ideas?
Thanks so much.
Nancy Dunn
Winco Ind.