Since upgrade, can't connect to internet on my p.c.

Question

After recent upgrade of Firefox on my p.c., I cannot connect to the Internet although I can send and receive email in Outlook. The error message says: Firefox is configured to use a proxy server that is refusing connection.
I'm sending this from my laptop after Firefox just upgraded again. Too many upgrades.
== This happened ==
Every time Firefox opened
== Firefox upgraded to 3.5.? I think.

Answer 1

The problem is that Windows Vista and Windows 7 treat all IP addresses as IPv6 so your PAC file will fail unless you make changes to it or Disable IPv6 completely or BOTH.
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WINDOWS 7 IPv6 disable (though I wouldn't, because it might screw up other M$ things)
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From this web site: http://windows7themes.net/disable-ipv6-windows-7.html
# Open up the registry.
# Uncollapse [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\]
# Next, we create a new 32-bit registry key: “DisabledComponents”: By the way, even if you are on 64-bit system you have to create a 32-bit registry key only, because it only reflects the size of the registry key. A 32-bit registry key can store a maximum value of 2,147,483,647.
# Enter: “DisabledComponents” when prompted for a name.
# Double-click the newly created registry key and copy and paste the value: ffffffff (8 F’s) [His documentation only has 6 f’s]
# Restart your PC and you are done: You just disabled IPv6 in Windows 7!
==============================================
PAC FILE CHANGES HERE
REMEMBER to change
var proxyONEip = "192.168.1.100";
var proxyTWOip = "192.168.1.200";
to YOUR FIREWALL IP addresses
==============================================
// alert ("Notice, This is a pop-up message\n***Use me to debug***");
function FindProxyForURL(url, host)
// Convert strings to lower case to avoid character matching issues
host = host.toLowerCase();
url = url.toLowerCase();
// Set proxy IP ADDRESSS VALUES here
var proxyONEip = "192.168.1.100";
var proxyTWOip = "192.168.1.200";
var proxy_no = "DIRECT";
// is client IP odd or even (if IP is ODD then
// proxyONEip/proxyTWOip else proxyTWOip/proxyONEip)
var myip = myIpAddress();
//DEBUG alert("My Addr: '" + myIpAddress() + "' \n");
//DEBUG alert("My URL : '" + url + "' \n");
// split the IPv4 address into a 4 element array
var ipbits = myip.split(".");
// make sure this is an IPv4 address, which is > 1
if (ipbits.length > 1)
// we have an IPv4 address here
//DEBUG alert("xIPv4 in play!\n");
//DEBUG alert("My ipbits.length = '" + ipbits.length + "' \n");
// grab the 4th octet and convert it to a decimal
var myseg = parseInt(ipbits[3]);
} else {
// we have a potential IPv6 address here
//DEBUG alert("IPv6 in play!\n");
//DEBUG alert("My ipbits.length = '" + ipbits.length + "' \n");
// split the IPv6 address into a 6 element array
var ipbits = myip.split(":");
if (ipbits.length > 1)
// looks like we have an IPv6 address here
//DEBUG alert("Looks like an IPv6 address!\n");
//DEBUG alert("My ipbits.length =:' " + ipbits.length + "' \n");
// grab the 6th octet and convert it from hex to decimal
var myseg = parseInt(ipbits[5],16);
} else {
// NOT AN IPv6 either, so ODD it will be by us forcing it to a 1!!!
//DEBUG alert("Looks like garbage, forcing to a 1!\n");
var myseg = 1;
// take the modulus 2 of the myseg where 1 = odd, 0 = even
var mycalcseg = myseg % 2;
if (mycalcseg == 1) {
// ODD number (mycalcseg = 1)
//DEBUG alert("My myseg odd is '" + myseg + "' - '" + mycalcseg + "'\n");
var proxyone = proxyONEip;
var proxytwo = proxyTWOip;
} else {
// EVEN number (mycalcseg = 0)
//DEBUG alert("My myseg even is '" + myseg + "' - '" + mycalcseg + "'\n");
var proxyone = proxyTWOip;
var proxytwo = proxyONEip;
// Bypass proxy for internal web servers
if (isPlainHostName(host)) { return proxy_no; }
var destinationIP = dnsResolve(host);
if (isInNet(destinationIP, "10.0.0.0", "255.0.0.0") ||
isInNet(destinationIP , "172.16.0.0", "255.240.0.0") ||
isInNet(destinationIP , "192.168.0.0", "255.255.0.0") ||
isInNet(destinationIP , "127.0.0.0", "255.255.255.0") ||
isInNet(destinationIP , "169.254.0.0", "255.255.0.0"))
return proxy_no;
//DEBUG alert("My PROXY = '"+proxyone+":80'; PROXY '"+proxytwo+":80' \n");
return "PROXY "+proxyone+":80; PROXY "+proxytwo+":80";
}