problem after malware removal

Hello,
After removing some nasty virus/malware from my system I have had a big problem, namely all my network connections have disappeared and all my network devices have stopped working. In device manager my ethernet card, wireless adapter and a load of miniports (don't know what they are) all have the yellow ! mark next to them and I can't even switch on my wireless adapter by pushing the button. I have tried to reinstall the drivers but to no avail. I have also tried to install a USB wireless adapter but this would not work either. Any ideas would be very much appreciated as I cannot access the internet whatsoever and this has been a long running problem.

Thanks in advance,

John