IIS listner service errors

ok, maybe someone out there will be able to guide me on this. We have a
website setup for an outside vendor, that sends us data through a HTTP
listener website. I was not involved in setup, but need to figure out why it
stopped working? here is the errors that are in event viewer. any direction
appreciated...

AL

Event Type: Warning
Event Source: W3SVC-WP
Event Category: None
Event ID: 2236
Date: 6/26/2007
Time: 10:01:15 AM
User: N/A
Computer: FTP
Description:
The server failed to load application '/LM/W3SVC/1402895825/Root'. The
error was 'Access is denied.