We've recently installed a new server running Server 2008 R2. I am logged in as Administrator through RDP. I am trying to add a new user group to a folder's permissions. I've right clicked on the folder, selected Properties, gone to Security Tab, clicked Edit, clicked Add, typed in the name of the user group, selected Check Names and a pop up screen appears asking me to Enter Network Password. "Enter the name and password of an account with permissions for the (domain name). I have typed in the Administrator username and password but it returns with a message saying" The following error occured while using the user name and password you entered: Logon failure:unknown user name or bad password". I know the username and password are correct but I can't get past this screen.
Server is located off site so not possible to make the changes locally.
Thanks for you help.