Every time I've tried a harness on a rabbitoutside, they always lead the way... It's not like walking a dog wherethey will follow you wherever you go. At least that's been myexperience.
But if you can, detach the leash from the harness and let your bun hoparound in just the harness part. And once she seems okay with that, tryputting the leash back on and let her hop around on her own (don'tholdthe leash.)
If you can't detach the leash from the harness, just let the bun hop around with the whole thing on.
When s/he hops around like normal with everything on, then you can hang onto the leash.
Whenever I'd take my rabbits outside, I'd just sit in a very centralspot holding the leash, and let them hop wherever they want to aroundme. That's another option, go sit in some grass somewhere and let yourbun hop around. Where are they going to go? THey're on a leash. But Iwould try to make sure it's a fairly quiet spot so it's not too scaryfor the rabbit
Hopefully that helps your bunny get used to the leash!