In addition, cmd.exe does not really like being launched with an UNC path as the working directory:

'\\emc-filer\etl\data\Jamaica\scripts\Modules' CMD.EXE was started wit
+h the above path as the current directory. UNC paths are not supporte
+d.
[download]

I think there is a registry patch to make it ignore that/not issue that warning, but I haven't used it myself.