It took me a while, but I figured out what I was doing wrong. I was deleting the http:// that's in that hyperlink box & typing in the www part of the URL. It kept coming up with a 404 error. But once I left the http:// in there & followed it with the www address, it worked.
'Cept, now that I spent all that time trying to figure out what I did wrong, I lost my editing window to go back to the post I wanted to correct.
As a rally coordinator, I'm supposed to have more time. I put in for a request, but I'm still waiting on it.