XML - Turn Internet Explorer Into A Handy XML/XSL Debugging Environment
By default, Internet Explorer has two drawbacks when it comes to XML debugging. First, documents aren't automatically checked for validity, just well-formedness. Second, when you "view source" on a transformed document, only the XML is returned--not the output from the style sheet.
Fortunately, Microsoft has published a simple tool kit that corrects these drawbacks and turns your Web browser into a decent debugger; it's called, appropriately, "Internet Explorer Tools for Validating XML and Viewing XSLT Output." Once installed, you'll be able to use options on the contextual menu (i.e., the pop-up menu when you right-click in the browser window) to validate the XML document you're viewing or to see the processed XSL output.
You can download the tools (for free) from https://www.neowin.net/news/internet-explorer-tools-for-validating-xml-and-viewing-xslt/. After you download, double-click on iexmltls.exe to unpack the tool kit files to a directory of your choosing. Then, go to that directory and find the files called msxmlval.inf and msxmlvw.inf. Right-click on each of the files and choose Install. Job done.