Webshield and Windows 98

[kmivens]

I have Avast 4.7 installed on Windows 98 and I have a question regarding setting up webshield to scan web pages.  I know that the Proxy server in IE has to be set to 127.0.0.1 and port 12080.  However I do have a web accelerator known as Slipstream that needs to have the proxy set to 127.0.0.1 and port 5400.  Is there a way that I can run both webshield and and Slipstream under Windows 98?

[DavidR]

I'm not sure you can achieve this with win98.

The normal way to do it is to add the other proxy port to the Redirected HTTP port(s) window (separate multiple values with a comma, see image) in the Web Shield settings.

Though I don't think that would work if you had to set the slipstream proxy in the same place the avast proxy as IE only allows for one proxy port value to be entered.
Where have you set the slipstream proxy ?

[kmivens]

The slipstream proxy is set up in IE, which is where the avast proxy has to be set.  When running Win 98, the redirected proxy port is grayed out and can't be changed.  I have setup slipstream with XP on a different machine using the method that you mentioned, and it does work.  However, it looks like this method is not available in Win98

[DavidR]

The ability to add ports in the web shield redirected HTTP ports works fine with XP, NT or win2k as they are able to use the web shield transparent proxy function, unfortunately win9x, winME can't. So it looks like you are out of luck on the win98 machine.

Welcome to the forums.

[lukor]

This thread should help you:
http://forum.avast.com/index.php?topic=21892.0

[DavidR]

Not that I doubt you lukor but, how does this work with win98 if the transparent proxy doesn't work with it and needs to be set manually in the browser ?

I take it that the changes in the [WebScanner] section of avast4.ini changes the web shield proxy from 12080 to that of the ISP proxy port to that in the browser's proxy settings ?

[WebScanner]
UpstreamProxyHost=proxy.address
UpstreamProxyPort=8080

[lukor]

David,
actually this UpstreamProxy chain works only when transparent proxy mode is not used (in Win98 we have no other choose so its easy.) WebShield simply uses the specified server and port (in this case it would be Slipstream proxy at localhost 127.0.0.1 : 5400) as a HTTP proxy and does not try to connect to the destination servers directly. Exactly the same way as Internet Explorer does when you configure it to use a proxy.

If the browser is configured to use a HTTP proxy (webshield or other) it uses slightly different HTTP headers and is prepared to understand slightly different responses from the proxy. E.g. it forwards FTP downloads via the proxy or handles the user authentication differently and so on. In this situation it is fairly hassle free to introduce another "upstream" proxy in the chain. One, two or ten proxies in the row make a little difference. In the redirect mode, on the otherhand, the browser acts like no proxy is in the way. It is not such a great difference but it needs some efforts to be the "transparent" proxy in the middle. Introducing the Upstream proxy in this situation would require more modification to the request/response data and might lead to all kinds of incompatibilities (especially when Java applets and other beasts are involved). So we have decided to support the Upstream proxy option only for the Legacy proxy mode, and introduce other options (like not ignoring the local communication and changing the redirected ports) for achieving the same effects when in the redirect transparent mode.

Hmm, it seems I made it little bit more complicated that it actually needs to be, but hopefully you'll understand.
Cheers.
Lukas

[DavidR]

Thanks for the feed back Lukas, yes I was able to understand, thanks again.