Need help removing a Rootkit, W32.Gammima.AG, a downloader and other hanger-ons

To the Major Geeks,

First of all, Thank You for helping users like me. I think it is amazing that there is a community of people who lend a hand to us users in need.

I recently attended a meeting where I uploaded documents onto a couple of memory sticks. I have been plagued with viruses ever since. My Norton Anti-Virus has detected Hacktool.Rootkit, W32.Gammima.AG and Downloader. There might be others.

In addition to my Norton anti-virus, I have downloaded Spyware Doctor (the free GooglePack version), Microsoft's Malicious Software Detection program, and AVG's free Anti-Rootkit tool. "Rootkit Revealer" did not work on my computer.

The first two programs identified and removed a number of viruses - most successfully last night in safe mode - including a Trojan and a Downloader. At various times they have claimed to have either blocked or removed the Rootkit and Gammima, but the infections remain.

Norton points to the file "c:\windows\system32\wincab.sys" as the source of the Hacktool.Rootkit.

I would be very grateful if someone could look at my HijackThis log below and let me know if there are additional steps I can take to save my computer. I am living in East Africa, and don't have access to the level of expertise I need to adequately attend to this. Thank you in advance for your help!

Computer Specs: Dell Inspiron E1505, running on Windows XP

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Edit: Removed inline Hijackthis log


Thank you again for your help. I really appreciate it. I am running out of options.


Hongera sana (good luck!),
RS