Trouble creating sitemap CS5

Hey everyone -

It's been a while since I've visted the DW forums, and I hope everyone is doing well.

I'm trying to create an XML sitemap for my personal blog. I've tried the built-in XML sitemap generator in DWCS5, but that sitemap seems to be more for collaboration than search engines. I then tried an online XML generator, added the generated text to DW, saved it as .xml and uploaded the file. Everything looks okay, but the file won't validate, and I get the feeling I'm supposed to be adding something to the generated content. I've searched and searched but I'm not familiar at all with XML or Schema so I haven't found an answer yet.

The xml file starts with the header from DW:

<?xml version="1.0" encoding="utf-8"?>

The next lines are from the online generator:

<urlset xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
<!--created with Free Online Sitemap Generator www.xml-sitemaps.com -->
<url>

<loc>https://example.com/</loc>
<priority>1.00</priority></url>
<url>
<loc>https://example.com/index.html</loc>
<priority>0.80</priority>
</url>
<url>
<loc>https://example.com/page2.html</loc>
<priority>0.80</priority>
</url>
</urlset>

Obviously there are quite a few more entries but they're all the same so they've been left out for brevity.

The error that shows up most often in the validator is:

Fatal Error: undeclared attribute prefix in: xsi:schemaLocation
At line 3, column 128
.9/sitemap.xsd">?<!--? created with Free
with the closing tag after the .xsd" highlighted in yellow. There's a question mark in the error that's not in the commented-out text - maybe that's a clue?

I keep adding and subtracting text from the first urlset xsi link and another error that sometimes comes up is:

Incorrect http header content-type: "text/html" (expected: "application/xml")

What am I missing? I searched the forum but found surpringly few threads, so maybe it's something simple?

Thanks for your time.