I did everything you suggested, and the test page printed beautifully. However, the downloads and photos still print in grayscale. I did not understand what you meant by "try printing using the newly added print queue copy (Copy 1) and check for any differences."
The issue is resolved! I contacted Microsoft Support, and it was as easy as scrolling down on the print menu and clicking "color" instead of grayscale. Since I am not familiar with Windows 10, I did not know how to use that menu.
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