Question : folder sharing

I have created a folder on my application server that is to be shared with all the users in my domain and the application itself.
I have granted complete rights to 'Everyone'on that folder.
But whenever one tries to access the folder through one link in application GUI it prompts for username and password.
User machines are in domain and server is on work group. Both user machine , server and the application get authentication from same LDAP server.

How can I avoid that authenticatin promt so that user can directly get access to the files on the folder.

thanks,
Rajnish

Answer : folder sharing

the server needs to be part of the domain as well.