I have been infected by the Nimda worm yesterday. I have unhook my pc from the network and began installing latest version of norton anit-virus as well as download patches for IIS 4 running on Windows NT 4. I have a problem. Since my computer is already infected by the worm, it might be already too late to install these pathes and security measure. How can I clean out all back-door issues this virus have left behind and make sure My computer is not infected anymore. I thought I cleaned out the infected virus by running FixNimda utility but the worm seems to re-occur again and again. Please advise or suggest on how to approach this issue. I would not want to reformat my hard-drive unless I absolutely have to. Thanks ahead.