Question: My bos insists that I configure our mail so that when a message is received sender will get a auto-reply message confirming that his message was indeed received by our company.

So is it possible to mark such auto-reply message somehow in order to prevent sender's auto-reply mechanism from sending auto-replay to my auto-reply message so that I don't end up in endless cycle of sending and receiving auto-reply messages?

Answer: 
No. 

You need an adapter for the printer to have a network port ready. Where the serial female connector is remark there is a screw, it's usually on those model to remove a controller card. 

Check [there](https://www.youtube.com/watch?v=jCnk7wOu51I) for how to install the adapter. 

It seem a older device, just worth to mention that if the adapter is not available online, getting a new model might help, as new model have even WIFI available.
i setup tills so can confirm that this isnt possible, basicaly the RJ11 you are referring to is not to communicate to printer, this is for Till to be connected to Printer so EPOS can sent a message via printer to Till to open.

RJ11 is only used to send a signal to till unit so it open and only pulses, not to receive any data.

Plus for printer you need drivers and through RJ11 you wont get drivers point blank.
You need to look for RECEIPT PRINTERS with BLUETOOTH OR NFC and they will fulfill your requirements, there are many in the market currently.