Malwarebytes shows this;

Malwarebytes’ Anti-Malware 1.51.2.1300
www.malwarebytes.org

Database version: 7993

Windows 5.1.2600 Service Pack 3
Internet Explorer 8.0.6001.18702

21/10/2011 15:31:49
mbam-log-2011-10-21 (15-31-49).txt

Scan type: Quick scan
Objects scanned: 236512
Time elapsed: 12 minute(s), 19 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: 0
Files Infected: 1

Memory Processes Infected:
(No malicious items detected)

Memory Modules Infected:
(No malicious items detected)

Registry Keys Infected:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\SETUP.EXE (Trojan.Agent) → Quarantined and deleted successfully.

Registry Values Infected:
(No malicious items detected)

Registry Data Items Infected:
(No malicious items detected)

Folders Infected:
(No malicious items detected)

Files Infected:
c:\Setup.exe (Trojan.Agent) → Quarantined and deleted successfully.

No mention of what the trojan was !