Can I use a custom not shielded cable?

In the manual says: “Use only the shielded Ethernet cable included”. But I want tu put the disk some meters away from router, so I have installed a cable that goes though the wall. It is not shielded, can I use it? If not what can I do?

Thank you

I use Cat5e unshileded cable that’s got to be about 15(ish) meters long that I made up myself and it all works perfectly.  Just make sure all the plugs and sockets are correctly wired.