By default, the ReportBuilder folder inherits the Integrated Windows authentication setting from the parent ReportServer folder. This default setting will not work if the client and server computer are in different domains (or if the client is authenticating the user locally). users will get HTTP 401 access denied errors and ClickOnce authentication errors such as "Cannot retrieve application" rather than the connection they expect.
To enable Anonymous access, do the following:
1. In Internet Information Manager, expand Web Sites, navigate to and then expand the ReportServer virtual directory.
2. Right-click Report Builder, and then select Properties.
3. On the Directory Security tab, in Authentication and access control, click Edit.
4. Click Enable anonymous access, and then click OK.
When you enable Anonymous access, users will be prompted for their credentials each time they launch Report Builder, even if they have already been authenticated to Report Manager.
For more information, please see section “How to Enable Anonymous Access on the ReportBuilder Folder”:
Please feel free to ask, if you have any more questions.