So sorry, I typed "directory" but meant "download". Everything else in my last post is correct: there's an "allow" entry for Download Manager in Norton Internet Security.
I don't see any port-forwarding option in my router (Linksys) management. As a test I removed the router from my configuration and plugged the DSL modem output directly into my PC. Still no go with Download Manager.
Any other thoughts? Thanks,
John