I found this page handy:
Based on that page, I would suggest using notepad or command-line edit to create the following two registry files:
(Please note: My lines of dashes are delimiters - do NOT actually use the dashes...)
proxy-off.reg:
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[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable"=dword:00000000
-----------------------------------------------------------
proxy-on.reg:
-----------------------------------------------------------
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable"=dword:00000001
-----------------------------------------------------------
Save these somewhere... I'll use c:\windows\ for this example...
Then, create yourself a batchfile... maybe "ieproxy.bat", and save it also to c:\windows (just to put it in the path, so you can Start->Run "ieproxy [on|off]"...)
-----------------------------------------------------------
@echo off
if %1.=off. goto off
if %1.=OFF. goto off
if %1.=Off. goto off
if %1.=on. goto on
if %1.=ON. goto on
if %1.=On. goto on
echo.
echo To start IE with proxy on, enter "ieproxy on".
echo.
echo To start IE with proxy off, enter "ieproxy off".
echo.
pause
goto end

ff
regedit /s c:\windows\proxy-off.reg
start iexplore
goto end

n
regedit /s c:\windows\proxy-on.reg
start iexplore
goto end
:end
cls
exit
-----------------------------------------------------------
Please do test this carefully. I have not tested this specific implementation, because it doesn't apply to my sitch...
(I have tested importing registry settings this way - but again, test for yourself, as screwing up the registry is a LOT easier than fixing it... Go in and export yourself a backup copy before you test this the first time, willya?)
Hope it helps.
