Select Options... from the View menu.
Select the Connection tab, and make sure the Connect through a proxy server setting is checked.
Below this, look to see if the HTTP proxy is already specified. If it is and the Connect through a proxy server box was checked to start with, then you need to write down the host and the port that it is set to use. Later you will use these to tell WebMask about this existing proxy.
Set the HTTP proxy to use address 127.0.0.1 and port 8080.
Internet Explorer 3.02 has a bug, such that secure connections will use the HTTP proxy instead of the Secure one. As a partial workaround for this, WebMask is able to forward (or tunnel) any such requests that Explorer wrongly sends it to another proxy.
If you have such a proxy available (e.g. SafePassage), then you will need to tell WebMask about this. Use the Tunnel "https://" requests to option on WebMask's General property page.
If you haven't got such a proxy, and you need to connect to a https:// URL, then you will need to temporarily disable the browser's use of a proxy.