[JACS]

I have a virus on my computer that will not allow Internet Explorer to stay open (it opens for a second and all of a sudden it closes) or let me connect to the internet. I went through the registry and found an entry titled Cognac. I looked that up online and it said it was a virus, so I went into the registry and deleted that entry. I have tried to run several virus removal programs, but it finds nothing. I have tried downloading HijackThis, but it will not allow it to be installed, therefore I cannot provide a log. I have also tried to download new virus removal tools onto the computer, but they will not finish installing. I have also tried downloading Mozilla Firefox to see if the virus was only affecting IE, but I couldn't get Firefox to download completely. I don't know what else to do to remove this virus! Please help! Thank you for any information!