A. what kind of a file is it? (extension)
B. how/what is serving the image - a link in an HTML page??? Could be the image tag contains invalid dimension information (for instance).
C. what is the URL you are suing to serve the image??
its very unlikely the problem is really with XAMMP, much more likely the problem is browser or URL related. (or a misunderstanding of the format/browser issues)
the SURE way to tell what is going on is to enter the files URL in the browser.