The instructions say "Download Combofix by sUBs from one of the below links." You don't need two copies. It's OK since you got one of them to run, just delete the one that wouldn't run and keep ComboFix3.exe.
Yes, I would have only downloaded one, but given the random accessibility of programs, I figured I'd play it safe.
Copied & Pasted contents of "mbam-log-7-17-2008 (02-26-08).txt":
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Malwarebytes' Anti-Malware 1.20
Database version: 960
Windows 5.1.2600 Service Pack 2
2:26:08 AM 7/17/2008
mbam-log-7-17-2008 (02-26-08).txt
Scan type: Quick Scan
Objects scanned: 37815
Time elapsed: 4 minute(s), 50 second(s)
Memory Processes Infected: 0
Memory Modules Infected: 0
Registry Keys Infected: 1
Registry Values Infected: 0
Registry Data Items Infected: 0
Folders Infected: 1
Files Infected: 6
Memory Processes Infected:
(No malicious items detected)
Memory Modules Infected:
(No malicious items detected)
Registry Keys Infected:
HKEY_LOCAL_MACHINE\SOFTWARE\rhccwwj0eg5v (Rogue.Multiple) -> Quarantined and deleted successfully.
Registry Values Infected:
(No malicious items detected)
Registry Data Items Infected:
(No malicious items detected)
Folders Infected:
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008 (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
Files Infected:
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008\Antivirus XP 2008.lnk (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008\How to Register Antivirus XP 2008.lnk (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008\License Agreement.lnk (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008\Register Antivirus XP 2008.lnk (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
C:\Documents and Settings\All Users\Start Menu\Programs\Antivirus XP 2008.lnk (Rogue.AntivirusXP) -> Quarantined and deleted successfully.
C:\Documents and Settings\Mike Gilson\Desktop\antivirus-2008pro.lnk (Rogue.AntivirusXP2008) -> Quarantined and deleted successfully.
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[recovering disk space -- attachment deleted by admin]