Mysterious hidden proxy settings

Well OK, not mysterious, and not really hidden.  And I did cause it, but since I had forgotten what I did, I had a hard time finding it.

Normally, to configure a proxy, you go into Internet Options -> Connections -> LAN settings.  At least that’s how you do it on XP; Windows 7 is different.
These settings are stored in the registry thus:
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
 I was trying to find a way to modify these settings from the command line, and include it as part of my “fix_routing” script (which needs a write-up).  So I tried some stuff, and it didn’t work, and I gave up and moved on.
This weekend, we set up a SlingBox at a friend’s place, and I found that I couldn’t connect to it.  TCPVIEW showed the program trying to connect to a bogus proxy, and I couldn’t find this anywhere in the configuration file.  Then I remembered my previous attempts, and had to search around for that information again.  Luckily, I found it.
There is another set of settings, stored in the WinHttpSettings key.  These settings do not show up anywhere.  If TCPVIEW is showing that an application is trying to connect to a proxy, and you can’t find where that is configured, try here.
Note: It appears that the REGEDIT search tool will not search inside a REG_BINARY key, which I suppose makes sense.  This was why a search of the registry for the proxy address resulted in no matches.
The only way to modify these settings, is via the PROXYCFG tool in the system32 directory.
C:\Documents and Settings\aujaha>proxycfg
Microsoft (R) WinHTTP Default Proxy Configuration Tool
Copyright (c) Microsoft Corporation. All rights reserved.

Current WinHTTP proxy settings under:
SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Connections\
WinHttpSettings :

Proxy Server(s) :
Bypass List     :  *.local;*.big.corp;10.10.*;<local>

I zeroed out this key, and things seem to be working again.

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