Without Fiddler running, what do you see inside Internet Explorer's Tools > Internet Options > Connections > LAN Settings screen?
Without Fiddler running, what do you see if you go to a command line and type netsh winhttp show proxy
I trust that you have restarted Outlook without Fiddler running?
If neither of those helped, please tell me what version of Windows and what version of Outlook you are using.
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