Images won't display - mapping problem?

My images are stored outside of wwwroot, and they do not display when I browse pages on my production server (it's a virtual private server on hostmysite.com) Everything works fine on my development server, which appears to be set up identically.

My site's pages are in C:\ColdFusion8\wwwroot.
My images are in C:\ColdFusion8\extMySales\topSiteImages. In order to access these images, I created a virtual mapping in the jrun-web.xml file (which is in C:\ColdFusion8\wwwroot\WEB-INF). I have 3 other virtual mappings defined in jrun-web.xml (for example, all my cfc's are in C:\ColdFusion8\extMySales\cfcs) and they all seem to work fine. Here is the mapping for the images folder:

<virtual-mapping>
<resource-path>/extTopSiteImages</resource-path>
<system-path>C:\ColdFusion8\extMySales\topSiteImages\</system-path>
</virtual-mapping>

Here is my code for a typical image: <img src="/extTopSiteImages/logoBig.gif" class="floatLeft topLogo">

But on my pages, a standard icon displays instead of my images, which I assume means the image cannot be found. Any ideas would be appreciated. (I have contacted the hosting company, but their tech support quality seems to be hit or miss, and they have not responded yet.)

Thanks.
Pete