FMC Route To/From Same Airport

[intjmastermind]

The FMC is not allowing me to enter the same airport as both the origin and destination waypoint. It returns an error that I am entering a duplicate waypoint and will not let me proceed. If I wanted to practice ILS or RNAV approaches at the same field I’m departing from, what’s the best way to put that in the FMC?

[jmarkows]

Can you start by entering just the airport and then adding an approach to it?

Failing that, can you add the airport, manually add an approach waypoint (IAF or similar), then the airport again and load the approach?