This is an unusual post but it might help few people who are trying to set up Wi-Fi connection with a Belkin F5D7051. This was tested on Ubuntu 11.10 32-bit.

 

CAUSE

During the installation of Ubuntu, the Wi-Fi has been successfully connected but after rebooting: no network interface (wlan0). This is due to a conflict between 2 modules: rt2500usb and rndis_wlan. In fact, there are 2 types of F5D7051 based on the Broadcom BCM4320 and Ralink RT2500USB chipsets. The problem is that both have the same ID vendor:product that is to say 050d:7051, so the kernel could load the wrong one. Here are the steps to fix the issue.

TROUBLESHOOT

The following solution is to blacklist the wrong module.

First of all, ensure that you have the right component by typing in the terminal:

lsusb

It should display something like:

Bus 001 Device 003: ID 050d:7051 Belkin Components F5D7051
802.11g Adapter v1000 [Broadcom 4320 USB]

Note that 050d:7051 is the unique identifier of the component and [Broadcom 4320 USB] is the based chipset. Then, check loaded modules with this command:

lsmod

If you see both modules: rt2500usb and rndis_wlan, edit the /etc/modprobe.d/blacklist.conf and add the following line at the end of the file (to edit you need to be root; if you have a Ralink chipset, replace rt2500usb by rndis_wlan):

blacklist rt2500usb

Then, unload the module by typing in the terminal:

sudo modprobe -r rt2500usb

Finally, save the file and reboot the computer. Hope it helps. 🙂