Folder auditing, windows 2003

I have a DC that is also a file server.  Its in a 2003 AD domain; I have a folder with a few files in it, and I wish to audit changes, deletes, writes to the folder and its files.  I've gone into domain controller policy, auditing, and turned on "success" for audit object access. I've also gone into the default domain security policy and made sure the same was set here.  On the DC/file server, I locate the file folder, right click and select security under properties.  Selecting advanced, on the auditing tab I have added the folder, the group USERS, and select success for write, delete, change...  Nothing is being written to the security log.  Ran a gpupdate on the workstations I was testing from, and the server... still nothing... Any ideas?

Thanks!!