SAP Business One SQL login error

I'm implementing SAP business one on my company and I'm getting an error. When I log in to SAP on 2 client computers, SAP is not finding the server by name. But if I change the name to the server IP address, it finds it, but then it gives me an error later on. I've also noted that I cannot connect to the SAP server from these client computers using Remote desktop using the name. But if I type the IP address I can connect normally. I think this is a network error, because it's not happening on all of my client computers. Does anyone know why this is happening and how can I fix it?