Every time I try to install Firefox, IE blocks it, saying "Firefox Setup Stub 23.0.1.exe contained a virus and was deleted.". How can I get it to stop blocking the download?
Can you post the link you are downloading firefox from? It is a possibility you are trying to install a non-official (and malicious) version.
if IE flags every download as malicious this by itself might be a sign of an infection of your system: http://social.technet.microsoft.com/Forums/ie/en-U
It doesn't flag every download as malicious, only the Firefox download. I tried all the solutions on the link, but none worked.
Try to get the full version of the latest Firefox release on the FTP server: