[17.2] Fanout via options not available

Hello all,

I'm working with OrCAD PCB 17.2 and I'm trying to use the fanout tool to help route a BGA.  The problem I'm running into is that the only via it will let me select is 'Net Default'.  I click the drop down box but that is the only thing available.  I have other vias defined in the constraint manager for these nets and I've verified with the route tool that it can see the other vias.  This is the first time I've used the fanout tool so maybe I'm doing something wrong.  Does anyone know what might be going on here?

Thanks,

Dylan