GPO: per machine proxy settings

Are the machine accounts located in those OU's also?

And you can't set the proxy in the user setting if you enable make proxy setting per machine.

I believe this set of articles will walk you through setting up your zones to allow you to correctly set the GPO's:

http://www.windowsitpro.com/Article/ArticleID/20468/20468.html

Generally when you make that change, on the proxy server, you ensure that the client automatically is configured by the ISA server. If you are not using ISA, you will need to consult the vendor's documentation.

You need to make a loopback policy so that the group policy is applied to the computer instead of the user. apply the policy to the OU that contains the computer objects
http://support.microsoft.com/kb/231287/EN-US/

try to make 2 ou's for each room. one for loosers and one 4 comps

Create GPO
Computer
Admin Templates
Windows components
Internet explorer
Make Proxy settings per machine,
But I dont think this is your problem
I think your GPO is not enabled, not linked, or blocked from the top

Sounds like what you need is an autoconfig script. Also known as a .PAC file. This can be accomplished using IEAK Internet Explorer Administration Kit. Basicall you creat a script or use IEAK to creat teh script. Place the script in a webserver then use a GPO to tie the script to your users. I will enclose a sample out of IEAK.
Ras.

snip...
The following function is another way to make a proxy selection based on specifying an IP address. This example, unlike Example 7, uses the function call to explicitly get the numeric IP address (Example 7 uses the dnsResolve function to translate the hostname into the numeric IP address).

function FindProxyForURL(url, host)
{
if (myIpAddress() == "999.99.999.99") {
return "PROXY proxy:80";
}
else {
return "DIRECT";
}
}
The myIpAddress function returns the IP address (in integer-dot format) of the host that the browser is running on.

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