W97M/Reiz is a destructive Word trojan.
When a trojan document is opened, it creates a batch file,
"Autoexek.bat", and an AutoRun file to the root of the "C:" drive.
When Windows is restarted, the AutoRun is enabled and when the "C:"
drive is accessed via Windows Explorer or My Computer the batch file
is executed.
The batch file shows a message:
Updating! This May Take A While...
Please Wait...
and then attempts to remove everything from the "C:" drive using
"Deltree" command.
[Analysis: Sami Rautiainen, F-Secure]