I was able to upload a static resource (a zip file with an image inside), and link to it without trouble in an 8.15.17 org just now. A screenshot is attached below (and perhaps confusingly, the image I used in my test static resource is a screenshot itself).
Did this come up while you were building something new, or is this an image component that has stopped showing an existing image?
Could there be a typo in the resource name or file name?
Also, it might be worth testing out an image component in a brand new page, connected to this static resource + image, in case there’s something specific to the existing page you’re working on.
