Malicious Removal Tools Update Message Icon

I received an update message icon from microsoft. The updates included security for Windows 2000, which is my OS system, and Malicious Removal Tools. Before the installation of these updates, the wired Internet connection in my computer was OK. However, after I installed these updates, my wired Internet connection failed. I tried to restart my computer, updated driver for my network card 3 COM 3C920B-EMB, but I could not re-establish the Internet connection. the wireless Internet connection at my sister's computer was OK, the wired Internet connection at my friend's computer was also OK