I would give Combofix a try in safe mode, as it uses gmer as a rootkit
detector and that might be what is sitting on the system.  Rootkits are good
at being stealthy.

Download
http://www.bleepingcomputer.com/download/anti-virus/combofix

How to Use
http://www.bleepingcomputer.com/combofix/how-to-use-combofix

Derek


On Mon, Sep 5, 2011 at 2:38 PM, Russ Cox <[log in to unmask]> wrote:

> How do you know if your computer has been taken over as a bot? My friend
> was told by her ISP that she was a bot. I scanned the computer with
> Malwarebytes, Microsoft Security Essentials, and Spybot. One trojan and one
> virus were removed, but she's still told she is a bot. How can you tell if
> that's true? Next step is to scrub her HDD and reinstall everything.
>
>         PSOFT maintains hundreds of useful files for download
>                    visit our download web page at:
>               http://freepctech.com/index.**php/downloads<http://freepctech.com/index.php/downloads>
>

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