Outlook broken after fiddler installed

2 posts, 0 answers
  1. Mark
    Mark avatar
    2 posts
    Member since:
    Jun 2016

    Posted 19 Jun Link to this post

    I am using windows 10, and outlook 2016.  I installed Fiddler and configured it for WinHttp and SSL and everything worked fine.  My internet settings are set to automatically detect proxy settings and I followed the documented settings for WinHttp configuration ("netsh winhttp set proxy netsh winhttp set proxy 127.0.0.1:8888 "<-loopback>").  As I mentioned, I was able to see all traffic.  The first strange thing that happened is that Outlook stopped working unless Fiddler was running.  If Fiddler was not running, I get just get disconnected message from Outlook.  I changed the WinHttp settings back, (netsh winhttp set proxy default) but the issue did not go away.  I tried changing the Fiddler SSL settings to just connect for browsers, but no change.  I tried to not connect to SSL at all, and unchecked the box which started fiddler as a proxy, but still no change.  I uninstalled Fiddler, but Outlook is still broken.  I went in and deleted the Fiddler cert but still nothing.  I am sure this is not a coincidence as I previously encountered this and rebuilt the system.  This is the second time I have seen this same behavior, only after installing and using Fiddler.  Any ideas how to fix it?

  2. Mark
    Mark avatar
    2 posts
    Member since:
    Jun 2016

    Posted 20 Jun Link to this post

    Figured it out.  It was not actually Fiddler, but the fact that I was using the wrong command to change the WinHttp proxy back for my configuration.  I used to use "netsh winhttp set proxy default" instead of "netsh winhttp reset proxy".
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