If you have protected the folder where your shopping cart software lives with a merchant ID user, and a PW of the key, then you should be able to access a test html file in that folder with that user/PW.
Try it with a simple user id and PW first to see if that works.
If you can’t do that, then you have a problem with an incorrect user/pw.
I’m trying to do the same thing with Unix…however I need SSL, which requires a dedicated IP…going to try to get one…maybe that is part of your problem btw…z
PS…Oh goodie…we’re at 5 pages…lol…z