Link the script to the user configuration.
Define it as a logon script.
Script. Save it as Disable_proxy.vbs:

Option Explicit
On Error Resume Next
‘Create a constant for the HKEY_CURRENT_USER object
Const HKCU = &H80000001
‘Define variables
Dim strComputer
Dim strRegistryKey
Dim objRegistry
Dim strRegistryValue
DIm binValue
strComputer = “.”
strRegistryKey = “Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections”
strRegistryValue = “DefaultConnectionSettings”
‘Connect to the Registry
Set objRegistry = GetObject(“winmgmts:\\” & strComputer & “\root\default:StdRegProv”)
‘Retrieve the current settings.
objRegistry.GetBinaryValue HKCU, strRegistryKey, strRegistryValue, binValue
‘Change the ‘Automatically detect settings’ box to unticked
binValue(8) = 05
‘binValue(8) = 13 – Enable this line to check the box instead of uncheck
‘Save the changes
objRegistry.SetBinaryValue HKCU, strRegistryKey, strRegistryValue, binValue 

It has been tested on windows 7 and it works great.

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