Fiddler not capturing traffic from browsers

I've been using Fiddler for quite a while, but all of a sudden it no longer captures internet traffic. I'm on Chrome 29 and Fiddler v4.4.5.1. I've checked all filters and rules and nothing is on. I've deleted my rules file, turned on and off capture traffic, and a few other things with no luck. I even uninstalled and re-installed Fiddler to see if that would help but to no avail.

What am I missing?

[Follow Up]:

  • Troubleshoot Filters has no effect.
  • I see no activity in the log tab beyond "Fiddler Running..."
  • I've tried multiple browsers and none show internet traffic in fiddler
  • http://localhost.fiddler:8888/ does not work
  • http://127.0.0.1:8888 works and shows the fiddler echo service.

Solution 1:

I had the same problem, but it turned out to be a chrome extension called hola (or Proxy SwitchySharp), that messed with the proxy settings. Removing Hola fixed the problem

Solution 2:

Not sure if this is relevant but I had the same problem with Fiddler after the last update (v2.4.5.0). I turned all filters off but still wasn't picking up any traffic. When I unchecked Use Filters on the filters tab, however, all traffic was picked up as normal. I'm still trying to figure out how I can use filters when just checking Use Filters box causes all traffic to be blocked.

Solution 3:

  1. Use Help > Troubleshoot Filters to make sure the traffic isn't getting hidden unexpectedly.
  2. Look in the Log tab to see if there's a note about Chrome Group Policy hardcoding the proxy.
  3. Update your question to mention whether other browsers' traffic is captured.
  4. Visit http://localhost.fiddler:8888/ in Chrome; What if anything do you see?
  5. Visit http://127.0.0.1:8888/ in Chrome; What if anything do you see?

If you find that steps #1 - #4 don't show anything, this means that Fiddler is unable to set your system proxy information; this might be caused by security or VPN software. (Group Policy can also prevent setting, but Fiddler will usually warn you if this is the case).

When Fiddler is capturing, click Tools > WinINET Options > LAN Settings and see whether the proxy is set properly (should point at 127.0.0.1:8888). If not, you might try running Fiddler elevated (as Administrator) to see if it makes a difference. It may be helpful to collect a trace using SysInternals' Process Monitor tool, filtered to Registry operations on the ProxyServer registry key.

If step #5 doesn't show anything, this means that you have a firewall or some other software interfering with connections to Fiddler.