Navigate the the location below in your registry and make the corresponding change.

Create or edit the existing binary value "EnableAutodial", and set the new value to "01 00 00 00" to enable autodial or "00 00 00 00" to disable it. 

This restriction can be used either on a per user basis by adding it to HKEY_CURRENT_USER or on a system basis by adding it to HKEY_LOCAL_MACHINE. 

Key:[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
Value Name: EnableAutodial
Data Type: REG_BINARY
Data:00 00 00 00 = disabled, 01 00 00 00 = enabled