We get a lot of questions about USB to Ethernet adapters. I'm going to try to answer most of them here, as well as give some helpful links and tips that should help you make an informed decision on your next upgrade.
What does it do?
If you want to add an Ethernet port to your computer, and have available USB ports. It's great for laptops that have a dead Ethernet port, or someone who wants to connect to two different Ethernet connections at the same time. The one sold at our website www.usbfirewire.com/unetwork.html is specifically for Windows computers. That is, Windows 98SE, 2000, XP, and Vista.
Can I connect a printer with it?
Definitely no. This isn't what most of the USB to Ethernet converters are made for. The problem is that the adapter is being reversed (Ethernet to USB instead of USB to Ethernet) and it's simply not made for that. Physically, it will connect. But, since it doesn't have print server capabilities, it won't work. If you want to connect a printer to your network, use something a USB print server from Linksys - or you could also buy one from the company that really built the first network print server, and that's HP with their JetDirect
Does it work with Mac?
Most USB to Ethernet converters you'll find on the market are not Mac compatible. So, what can a Mac user do if the ethernet port goes out, but don't want to pay a bundle to get it fixed? You buy one that is compatible. See the one I found here from Apple.com; there are also one or two more I found, but I have not tested any of them. And for $29 bucks direct from Apple, it's a reasonable price.
Can I connect my hard drive to it to share files?
Again, this is another definite no if you're using this adapter. The USB to Ethernet would be working in the reverse, and thus wouldn't do anything. Physically, you could connect it. But it wouldn't work because of the electronics within the adapter not allowing it to function. The good news, however, is that you can share your files from a hard drive without a computer. One popular solution is something called a NAS. Here's a great wiki page that details it Wiki NAS Link. I found this link from PC World that showcases a few of the them for sale. They seem to show NAS devices that are more geared towards business and higher end users. Home users can find cheaper solutions on outlets like eBay.
This should give you a good outline on the mystery behind what USB to Ethernet converters are for, and what they're not for. What they can and can't do. And where you can find solutions to things that you're looking for. Good luck in your quest for a solution!