I'd thought that I had committed all the possible MySQL configuration mistakes, but along comes Dreamweaver MX with a new challenge--Error 404, with two possible reasons:
1) No testing server. (Impossible!),
2) The testing server specified for this site does not map to the http://test.xyz.com/_mmServerScripts/MMHTPDB.php URL.
My local machine has access to the MySQL server, and I am not using uppercase or weird symbols in any of the pathnames. Several working non-dreamweaver connections have been established with the MySql server both from my sites on DH, and from my local machine.
I suspect that the problem is in the site definition, but where? Does anyone have a working sample definition they could show me (i.e. not the localhost examples in the F.M.'s). Thanx.