Running at 10 mbps

There's possibility that the network (router/modem/switch) you're trying to connect has limit to up to 10 Mbps only. Or it can be that the current LinkSpeed of the Ethernet adapter might be forced to 10 Mbps. Do the following to check this setting:

1. Go to Control Panel> Network Connections.
2. On Network Connections, look for Local Area Connection (for the D-Link adapter). Right click it then go to Properties.
3. On Properties window, click Configure button.
4. On the next window, go to Advanced tab.
5. Look for Media Type, Connection Type, or LinkSpeed and Duplex Mode.

If the value is set to Auto Negotiation/ Auto/ AutoSense, try to force it to 100 Mbps.