Well... I thought I'd look a bit closer at the registry to see if the path "C:\Program Files\Common Files\Symantec Shared\VirusDefs" was in fact stored in there. Sure enough it is, except that it's stored in 8.3 instead. The location is HKLM\Software\Symantec\InstalledApps "AVENGEDEFS" REG_SZ, "C:\PROGRA~1\COMMON~1\SYMANT~1\VIRUSD~1"

In fact, the pattern folder is stored in the registry as well.. The location is HKLM\Software\Symantec\SharedDefs in two values, DEFWATCH_10 and NAVCORP_70 as "C:\PROGRA~1\COMMON~1\SYMANT~1\VIRUSD~1\20011026.021"

Before you tell me my pattern is out of date, I know the newest is the 31st. I'm on my home machine (unmanaged).

You know, I did a quick search of the reg for the path before I wrote that code, but didn't think to search for the 8.3 variant.