Bluetooth: Old - Handoff/Airdrop2 not supported

After running EtreCheck got "Bluetooth: Old - Handoff/Airdrop2 not supported" .

I'm trying to get airdrop to work with my MacBook air. How to update the bluetooth if possible.

iMac (27-inch, Mid 2011) (Technical Specifications)

iMac - model: iMac12,2

1 2.7 GHz Intel Core i5 CPU: 4-core

20 GB RAM Upgradeable

BANK 0/DIMM0

8 GB DDR3 1333 MHz ok

BANK 1/DIMM0

8 GB DDR3 1333 MHz ok

BANK 0/DIMM1

2 GB DDR3 1333 MHz ok

BANK 1/DIMM1

2 GB DDR3 1333 MHz ok

Bluetooth: Old - Handoff/Airdrop2 not supported

Wireless: en1: 802.11 a/b/g/n