I am trying to open an XML data file (I think). I am having trouble
following the Help instructions. The instructions say: click on File
Open, then select and open the file. An Open XML dialog box should appear.

It does not. Instead, the open proceeds directly, but the resulting
worksheet does not have useful data.

What am I doing wrong?

Using Notepad to view the file contents, they seem okay. I don't know XML.
But the file does contain the data I am looking for, albeit in a structured
form,

I suspect the problem might be the hacks I have done to get this far.
Perhaps I made some mistakes.

The file was downloaded from a web site. The file extension was ".pwx".
Since the system does not recognize that file type, I renamed it to ".xml".
Excel recognizes that. But I wonder: are there different flavors of XML
files; is there a different file extension that I should use?

As I said, I don't know XML, so I don't understand much of the terminology
in the XML Help pages.

If I have to teach Excel an XML schema first, then f'getaboutit!

I don't know what an XML Expansion Pack is and whether or not I need one. I
do not see XML on the Data menu anyway. Is that a symptom of the root cause
of my problem?

I'm about to resort to writing a VBA procedure to read and parse the file as
text. I hope someone can save me the trouble.