Small Business Server & Proxy Server

I have a client thats running SBS and a proxy server. Since I have never had any experience with Proxy Servers I require a little assistance and hope some one can help.

There are 4 workstations that connect to the server running 95-Me.

Thingsworked ok 1 day but the next day they get a screen coming up with the heading “Source Text For Defaulf Internet Web Site” and goes on mention using Front page etc.

This error seams as if the web site is not available as I have dont a search for this and got various sites that display the same information.

If I turn off the Proxy server settings in Internet Explorer you can access the Web OK.

I dont know where to start looking CAN YOU HELP!!! PLEASE