For certain dynamic OPMLs, you may need to set authorization information in order to retrieved the OPML file from its located place on the Internet. Following shows how to set that information:
- Open context menu of that dynamic OPML
- Select 'Properties' menu option, which opens up the 'Properties Dialog'
- Switch to the 'Synch' tab
- Check the checkbox called 'Authorization is required'
- Enter the correct username and password
- Click on 'Apply' button to apply this change