There is no way to stop this unless you just kick him off the computer.. There is always a way to get around a program, and if he hasn't found out how yet.. He will. I do, it's very simple stuff.

It appears that he is not all that tech savvy or else he would not be using internet explorer. Simply put passwords on all the administrative accounts and give him limited access if you are using Windows XP. Never leave a computer unattended if you are logged on with an administrative account and pick a good password. Then just limit the stuff he can do, it does not look like he knows how to crack admin on Windows XP. If you do not know how and what to limit on his account, then have a professional help you.

Oh, and don't get Vista right away. Wait about a year because there will be a big problem with security holes. This is said about most operating systems but it especially applies to Vista because of all the hidden "features" Microsoft puts in so that Vista won't be pirated as much as Windows XP was.

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Edited by Lt_Flippy at 01/31/2007 7:29 PM

There are quite a few possible ways and each can be broken. I will give you a few possible solutions and the downside that might occur afterwards.

1) Software filtering-monitoring software. This is the most common form used by households. It probably is the easiest to set up and use, has a lot of features, and pretty cheap.

How it works: What you do is install it into your computer. It will run in the background invisibly (depending on what you buy and all of them HAVE to be running so there are ways to shut it down). As well, depending on the software, it can block certain sites, allow other sites, block certain types of programs, take screenshots of the programs and websites, log all conversations and keystrokes, and many other things. As well, it will make a report to the user usually through email and other methods.

Problems: It may conflict with anti-malware programs. Because of how it works it acts a lot like spyware (it actually is spyware) and sometimes it will be thought to be bad and blocked from working properly. Make sure there are no conflicts before hand. As well, whitelists and blacklists can be beaten through proxy severs and tunneling.
How this works is it uses a site that is allowed and bounces all the traffic through that site. An example would be going to Google and looking at the site through their cache program so the filter thinks they are on Google while they are looking at content from a "bad" site. This can be stopped through using a filter that actually reads the site that is coming through. However, that can be bypassed by doing something like a Google translate to another language. That way the filter will think it is coming from Google and also see any bad words so it will display but doesn't mean it is a safe site.
Another problem may be reading through the logs. I test ran a program once and the logs were so big I had a tough time reading through it all.

2) OS blocking controls. XP and new Vista offer some control.

XP: It is pretty tough to set it up in XP but it would be like what schools and businesses do. Mostly it is to protect the computer and not really filter or block. But from what you said I can see it working a bit for you. XP allows you to restrict what a non-admin can do (such as make changes to settings). But I don't really recommend it as it is really easy to bypass them.

Vista: I am unsure of exactly what Vista does so I can't really talk about it. The problem with using the OS is how inflexible it is. I do not know how it figures out what is going on within a program and how that works. I wouldn't recommend using something that is brand new and not yet openly tried in the wild.

3) Hardware filtering. This is probably the most expensive. This is how businesses operate. They filter what happens at the router/server. Most routers allow you to block sites and even use word blocks.These are a bit tougher to fool as it isn't on the computer so they have less access to it. However, it can be fooled just like the other two through the Google style tricks. That is the problem with asking a computer to do something that only a human can. A computer can't really understand what is "bad" and what is "good."

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You win some, you lose some. But in the end, just make sure you beat the crap out of your enemy.

Ok I have a question and I'm hoping someone can give me some help. Seems my husband and I have a very "computer savvy" teenage son (big shock). We've tried just about everything to prevent him form doing things he shouldn't on the computer. We've given the kids a limited account on the computer, to prevent them from downloading things and to prevent them from changing settings. The son has figured out a way around things...He goes into internet explorer/internet options and deletes the history or sets it so it saves "zero" days of history so we can't find out where he's been. What I want to know is, is there anyway to prevent him from deleting the history/changing the settings? Or is there a way to block internet explorer all together? On his MSN account, we have parental controls, so what he does is just go right into internet explorer and when he sees us coming, he just closes it out!! The computer is in our family room, thought that would cut down on his "tricks" but short of sitting right there with him or taking it completely away, I don't know what to do anymore. Any suggestions? Really frustrated here!!!