A web page/site that an automated "problem solver" sent me to some time ago might be more helpful to you than it was to me on that occasion:

http://blogs.technet.com/swi/default.aspx Microsoft Security Vulnerability Research and Defense.

This page is a "Microsoft Blog" but differs from most other blog pages where Mickey sends you to look for help in that only "official" posts/posters participate. It's thus free from the "self-proclaimed genius" comments that you have to wade through and ignore on the more public ones, but it is addressed to "developers" and professional IT managers so it's probably "too tech" for most of us.

Note that it's a very long page, so you have to scroll way down to see all of the subjects currently posted. There also are archive links in the right sidebar.

I don't see anything at the current page that I recognize as helpful for the problem you've described, but you may be able to make a better connection to your problem.

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You mentioned that Windows Update is redirected to MSN and that Google links are redirected but you can type them in the addy bar and get to the site. In my Vista, update opens as a Control Panel section, so I can't easily tell what the connection is, but it might be of help that on Lin's WinXP pro SP3 machine, her WinXP Microsoft Update is at:

http://update.microsoft.com/microsoftupdate/v6/default.aspx?ln=en-us

If you can get to the update site and get Guardian up to date it might help.(would the Trojan have disabled the link if it wasn't helpful?). If clicking the link here doesn't work, you can copy the "display string" and paste it into the URL space, or type it in manually. One or the other may get you to a usable connection, or you may be able to read the URL you've been using from RtClick Properties for the link. If you can't read it from the Start Menu, right click and send a shortcut to desktop and try reading the URL from the shortcut properties(?).

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The very intimate connection between Windows Explorer and Internet Explorer is visible in the ability to open a location on your own computer or on an internal network in Internet Explorer. At Start | Programs | Accessories | System Tools there's a "maintenance link" to open "Internet Explorer (no add ins)." If you use this link to open IE, it should open a blank page without even a home page showing, and the IE instance will have NO ADD-INS loaded. If you put a drive letter ( e.g. X: or X:\ ) in the address box, it will (or should) display the drive in Windows Explorer. You should get a warning that it will connect in "unprotected mode," but this mainly means, in this case, that the target drive doesn't show a "security certificate" and/or isn't a "normal page."

You should be able to use whatever "identity" you normally use for a network drive, but it may be more convenient to map one (Windows Explorer | Tools | Map Network Drive) to give it a drive letter on your local machine. If (????) the network drive opens and is visible using the "no add-in" IE route, it would strongly suggest that your problem is embedded (or is executing through) an IE add-in.

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Perhaps a last resort is to ask for help from Microsoft. At microsoft.com, on some support link or another (it moves around) you should find a "support using web chat" link, sometimes on a "contact us" page. In most cases, they'll refer you to "phone support" if you present your case as a problem that appeared with a Microsoft Update. (Asking for help with an update at web chat is the simplest way I've found to get the current phone support number for your location, but if you find a direct link to the number you can use the one it gives you.)

Support is free for problems with updates; but the vmail choices at the phone support numbers don't let you tell them that's why you called. The key to getting in is that when they ask if the software was installed on your computer by a manufacturer you must say NO. (You are calling about the patch software installed by Microsoft, and not about the OS installed by your OEM.)

If you can get past the recorded choices, you should reach an actual person, where you can complain that "since the update on (date) my machine is all crappy." If/when they decide it's not a patch problem they'll probably ask for a credit card number, at which time you can just say no and hang up, but sometimes you'll glean quite a bit of helpful assistance without having to yield to the extortion. (A good tech support person really hates to quit without a solution; but they're not all that dedicated.)

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I don't really know if any of this will help, and I don't know if you know that I know that you probably already know about all of it. Just some thinking out loud.

John