Could you check the following article in case there are some methods you haven't tried yet:

How to set the home page

I have tried doing all the different ways, including those in the article, and they do not work - or at least I can't get them to. This is a new computer.

The home page is the one that appears in new windows (for example, Ctrl+N). That doesn't show your Custom URL? What does it show?

If I'm understanding you correctly, it doesn't show any URL, just the Firefox symbol. My myMSN home page is pinned to the Firefox page and if I click on that it takes me to the place I want to go. On my old computer if I just clicked on Firefox it would take me to myMSN as the Firefox home page with no other steps required.

Sorry, I wasn't clear about what to compare. On the Settings page, Home panel, can you confirm that your MSN page address is listed under Custom URLs? If that doesn't have the right address, can you paste it in there?