I've been using the same public Wi-Fi (staying in a guesthouse) for over a week now.

But this morning for the first time I got this puzzling warning from Windows Firewall:

Windows Firewall has blocked some features of Google Chrome on all public and private networks

Why does Windows Firewall want to block one of the world's most popular web browsers today after being fine with it for years, and being fine with it on this connection for a week?

Could it hinge on the words, some features? If so could it be something like a rare or new feature of Chrome that uses a different HTTP port? And if so why doesn't the security alert tell me any more about it?

Or could it be a known bug in Windows Firewall?
Or perhaps a known virus etc attaching itself to Google Chrome?
Or is there a chance it's related to "Other browser makers follow Google's lead, revoke rogue certificates"?

I haven't restarted Chrome for days and have downloaded but not installed a Windows update from a few days ago. So I'm not sure what may have managed to change on my machine since yesterday.

  • I think the reason behind this is a toolbar or an addon within chrome...
    – user165733
    Dec 18, 2013 at 2:04
  • Hmm I loathe toolbars and abhor addons. I've judiciously installed (or coded) a few but none of them have been updated since yesterday when I used Chrome without getting such a warning. Dec 18, 2013 at 2:24
  • Because Microsoft likes to push their own useless browser(IE), I got the same thing when trying to install Firefox.
    – user270595
    Dec 18, 2013 at 2:27
  • 3
    @Slowki Please don't make up reasons that don't exist. This has nothing at all to do with pushing IE (which is also far from 'useless' in its latest iterations, but I digress).
    – Bob
    Dec 18, 2013 at 2:35
  • 1
    This prompt only appears the first time an application is trying to listen for connections. That’s not what a web browser is supposed to do.
    – Daniel B
    Dec 26, 2014 at 22:31

2 Answers 2


Google Chrome updates itself without asking you first (Firefox does the same - nothing sinister, just makes sure you always have the latest security patches), and this is separate from Windows Update. Since you're on public wifi, Windows Firewall is stricter about changes to network-accessing software than it would be on a network you marked as private.

  • Google Chrome downloads its new updates in the background but it shows a coloured symbol to let you know that it's out of date and only actually starts running the new version when you restart. I've typically got many tabs open and only sporadic Internet access so I only restart Chrome when I specifically get the time and connectivity to do it properly. (I'm hitchhiking in China.) I have now restarted a few times since asking this question but not at the time. I haven't seen this happen again though. Jan 11, 2014 at 5:21

Google Chrome opens an exception TO the Internet, but also opens and exception FROM the Internet - allowing it an open door to your system. Blocking this feature by unchecking the exception is what I do, or not allowing it to make the exception in the first place.

  • "opens an exception from the Internet". Wrong. You'll need to setup NAT on your Internet router/firewall for that to happen
    – mcont
    Oct 5, 2016 at 16:09

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .