Genymotion unable to connect .....

• Your network adapter can be misconfigured:

  Edit the Host-only Network that is listed in the network category of the File/preferences menu of VirtualBox (VirtualBox/Preferences on Mac OS X).
  The adapter's IP address has to be in the same network (192.168.56.0/24 by default) as DHCP server's IP address and DHCP's IP address bounds. If all those addresses are not in the same network, then your Genymotion virtual device might not be able to start.
  You can also remove the Host-only Network. Genymotion will automatically recreate it at the next virtual device start.

• Your firewall may block the application

  Please check your firewall rules

192.168.1.0/24表示网段是192.168.1.0，子网掩码是24位，子网掩码为：255.255.255.0，用二进制表示为：11111111 11111111 11111111 00000000 ，这里为什么是24呢，就是因为子网掩码里面的前面连续的“1”的个数为24个，一定要连续的才行。