Automatically Detect settings in Internet Explorer getting unchecked

Hi All,

I am facing an strange issue here in browser configuration / Internet setting.

I checked "Automatically Detect Settings" checkbox in Internt Options->LAN Settings.

After sometime, this is getting unchecked and "Use Proxy Server for LAN" option is getting checked automatically.

Anyway to keep "Automatically Detect Settings" checked always instead of "Proxy server".

I tried below ways.
1) Through group edit->Administrative templates.

2) Tried disabling the Automatically detect setting and proxy server checkboxes.

3) Tried setting ProxyEnable to 0 in HKCurrent User \Software\Microsoft\Windows\CurrentVersion\InternetSettings\ProxyEnable to 0.After sometime, it gets reverted to 1.

Above steps not worked.

Due to this issue, navigation to websites though scripts are failing with error "Proxy server not responding".

Any input appreciated.

Thanks,
VVP