According to the Kaspersky website today:
On September 22 at 2:00 pm antivirus databases were located on the Kaspersky Lab server. Using the server, wextract.exe file is detected as Trojan-Dropper.Win32.agent.vj. This is Kaspersky Lab false positive. Updated databases with the false positives deleted have already been located on the server.
Raaar, well "already" isn't soon enough to have utterly unmade my day!
Being a good (ar)soul I was running Windows Update on my boss' computer whilst she was away. However something nasty happened, by coincidence, just as the Windows Genuine Advantage Validation Tool was installing, and lo, I ended up deleting something whiffy from C:\WINDOWS\SoftwareDistribution\Download blah blah blah.
Cue a Windows File Protection warning - "Files that are required for Windows to run properly have been replaced by unrecognised versions. To maintain system stability Windows must restore the original versions of these files." In true Pulp Fiction style, lets go back to that first sentence. Piss. I wouldn't have care so much if it was my own computer...
It reminds me of my a problem that happened when I used to have Norton Antivirus 2004 (version 10.0.1.13) installed at home. Running Live Update the following error flashed up:
Error: "LU1812: An update failed to install. A program that was part of this update failed when it ran. This update was not applied."
Further analysis revealed:
Symantec Common Client Update - LiveUpdate has determined that this machine is running a pre-released or beta version of a 2004 Symantec product. This version of the software is not supported by Symantec and cannot be updated. Please contact the vendor that you purchased the software from to request a released version of the software.
Starbuck's troubleshooting solution: Uninstall Norton antivirus. Don't forget to uninstall the bits which the uninstall won't touch via Add/Remove programs. And delete those sticky boot tweaks as well (e.g. Norton eMail Protect - C:\PROGRAM FILES\NORTON ANTIVIRUS\POProxy.exe NAV definition alert - C:\PROGRA~1\NORTON~1\DEFALERT.EXE Norton AutoProtect - C:\PROGRA~1\NORTON~1\NAVAPW32.EXE /LOADQUIET)
And finally, download some decent freeware - AntiVir will do.
Et voilà, good antivirus software, no rip-off charges, and a massively speeded up machine as a freebie bonus.