One of two ways,
1. Use a custom policy for IE to lock the settings. You can use ZFD to distribute this policy, or you can go to each system and apply the policy, or if you have a domain, you can apply it there. If you are not familure with programming a filter excpetion list with in BM, this would be your easiest way to go. You can also download IEAK from M$ and create a custom install of IE that has the proxy setting in it already and a policy with it also. I last used in with IE5.5, not sure on IE6.
2. Don't allow people to browse the web with out using the proxy. By default, the BM filters set this up for you. A filter exception you put in your self is what opened up everything. Fine tune your filters, don't just open up everything to get some program to work. This would be the most efective way. People can mess with thier systems and break through a policy if they know what they are doing. Blocking access at the gateway forcing people to use the proxy at the gateway will make their efforts pointless.
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