Trouble installing RS485_protocol library on arduino 1.8.3

I am recently working on building a communication system involving multiple arduinos and plan to use RS-485 modules as the distances I need to cover are fairly large (in the order of Km).

But , the problem is that, I am unable to use the RS485_protocol.h library. I installed and imported the zip file into the IDE , but everytime I get an error message saying that such a library already exists.Directly using (#include " RS485_protocol.h" ) along with the softwareserial library gives other error messages like "no reference to sendMsg and recvMsg". I have also tried installing the HardwareSerialRS485.h library , but with no effect . What to do? Plz help me out.

Where are the links to these libraries? Did you really read the sticky post at the top of the topic?

I got the links from Nick Gammon's forum on the topic of RS485 Serial communication.

I got the links from Nick Gammon's forum on the topic of RS485 Serial communication.

Did you read that post now?

Post the links here! Don't expect us to search for them!