You can do some basic testing without needing a phone or using someone elses connection.
1) Go here:
https://www.grc.com/x/ne.dll?bh0bkyd2 2) Click on Proceed
3) In the box under where it says "You may select any service from among those listed above . . ." enter "8075-8085"
4) Click where it say "User Specified Custom Port Probe".
5) After a few seconds you get a report with three columns. Scroll down to the entry for 8080.
If the router is connectly configured it should say:
8080 OPEN! http-alt HTTP Alternate (see port 80 and port 81)If the router config has a problem then it will say:
8080 Stealth http-alt HTTP Alternate (see port 80 and port 81)It's worth trying several times because Shields Up! uses a very short timeout and sometimes the TiVo doesn't respond in time.