unable to assign domain user permissions to workspaces

[sonun]

I have a win2k domain in which I have set up users and groups.
I have setup a Sharepoint Portal Server which I have added to the domain previously mentioned. I have created workspaces in Sharepoint and I am trying to assign them users and groups. Under properties I goto, Security, browse down to the group or user (created on the domain controller) I want to add and when I click 'Ok', t says it is uanble to do so and gives methis error.
"Processig of the object (object name which is the user or group name I was trying to add) failed with the following error: The specified domain either does not exist or could not be contacted"

Now, I logged into domain when I logged and I was able to setup some shared folders and assign them domain group permissions.

So, whats wrong.

Please advise.
Thanks.

 

[sonun]

One other thing about the domain controller is that, I have not installed DNS or WINS on it.
Thanks.

 

[sonun]

Anyways, DNS was the problem.
I used the hosts file to temporarily resolve the problem.
Thanks.

 

[PHead2]

You can't have a properly functioning domain withour DNS (in 2K and up)....