iOmega MiniMax external hard drive not appearing on my computer

Trying to connect my iOmega MiniMax 1TB to my MacBook air, it is very old and has not been used in at least 5 years. I do not have the cable that it came with and so have used a double-ended USB cable. Is this okay? It does not show up on my desktop or in the finder even though the light is on and I can hear its fan working. Any advice?