I have a similar issue with SPB16.3. My install was working, but now will not netlist for Allegro. I have reinstalled it twice, including the latest Hotfix I have. There is no output in the Session window when I try to run it and all of the configuration fields get cleared every time I start it.
I can select the .cfg file, but when I try to edit it, I get error ORPXLL~1 (The parameter is incorrect). I can't tell if an .exe file got correupted or what, but I can generate netlists for other file formats, which by the way, does me no good.