Follow these steps to change the Physical Path Credentials option for the hosted Bold Reports® application:
Open Internet Information Services (IIS) Manager by typing inetmgr in the Run dialog box (accessible through Start menu).

Navigate to the Sites section in the navigation pane on the left, then select your Bold Reports® application.
Right-click on the Bold Reports® application and select Manage Website > Advanced Settings.

Set the Physical Path Credentials field to Application user (pass-through authentication). Click OK to save the path credential changes, and then click OK on the Advanced Settings prompt.

Right-click on your Bold Reports® site and select Manage Website > Restart to refresh the changes that were just made.

Now, you can log in to the Bold Reports® server.