I just picked up a Solo yesterday, took it home and flew it for about an hour. Everything worked great. The previous owner threw in a Nexus 7 for controlling it, so after I threw the batteries on the charger, I upgraded android on the Nexus and realized they had made a custom wifi password on...
after having great difficulty getting past preflight update screen and performing factory reset this is procedure that got me in the air,
1- Power off the units and close the Solo app
2- Perform a factory reset to the Solo and controller, make sure the orange light underneath the Solo blinks...