На примере Reporting Services
For the other question “A login dialog appear while accessing Report Manager using Firefox”, this should be caused by the FireFox does not pass the current user’s credential to the Reporting Services automatically.
To solve the issue, we have to enable windows authentication on our domain.
1. Open Firefox
2. Navigate to the url about:config
3. Locate the following preference names and put as the value the comma separated values of the address roots (double-click these preference).
Our value should look something like this: server (the server name of the report server)
Now, the login dialog won’t be happen while accessing report server or report manager.
Источник – http://social.msdn.microsoft.com