If you are not a power user, like me, of Fiddler2 (or even a non-power user) you may run into the occasion where Fiddler simply stops capturing your traffic it can be very frustrating.  Today this happened to me, well technically I caused the issue a few weeks ago, but just noticed it today.

If you are like me when this happens you are going to jump out to google and look for an answer.  Most everything I saw out there pointed me to my  WinINet settings or the Fiddler Options (below)

After looking at my settings and making various pointless changes nothing solved my problem.  I than moved on to the ‘lets see if uninstalling/reinstalling dance’ solves my problem, which of course it did not.  Right When I was about to declare my machine ‘fiddler broken’ I by chanced clicked on the "Filters” tab

and noticed that turned on Using Filters and was ONLY accepting traffic from one IP Address as below

After turning off the ‘User Filters’ option my traffic was being monitored again…. wow that was difficult.

The moral of the story is this.  If you turn on filtering in Fiddler you may want to turn it back off prior to leaving the application because chances are you will forget you turned it on a few weeks later and you will pull out your hair trying to find out why your traffic is not being captured.

Hope this helps some other poor sap like myself.

Till next time,