Downloaded Firefox Portable from https://portableapps.com/
Then used https://www.virustotal.com/en/ to scan the file for virus and found two viruses. See link below.
https://www.virustotal.com/en/file/506b62f6fef055db4524cb4ab3d6a8a602c2d...
Does the program have a virus?
That doesn't mean two viruses. That means those two antivirus apps have false positives. Luckily they're very minor ones. You can try and report the error to them if you'd like. Anything that actually has a virus looks like this: https://www.virustotal.com/en/file/b7937ca1d56a671fe5527b400b858328ed388...
Sometimes, the impossible can become possible, if you're awesome!
Thanks John, for the clarification.
P.S. like your mantra: "Sometimes, the impossible can become possible, if you're awesome!"
I know I am bumping an old thread BUT Norton Antivirus keeps deleting Firefoxportable.exe because it "thinks" it has a virus (WS.REPUTATION.1). I have excluded it from scans but it keeps getting deleted on other computers. Latest FF (48.0) and latest NAV updates.
That flag just means that Norton hasn't seen many instances of a file. It's a (bad) addition in later versions of Norton. It doesn't matter that FirefoxPortable.exe is (1) clean, (2) open source, and (3) digitally signed with a certificate verified by a third party. You'll need to report the issue to them or disable reputation-based flagging (if it even lets you).
Sometimes, the impossible can become possible, if you're awesome!