Hello fregas baratis,
I am sorry for your frustrations. We should have made this clearer.
we have separate extensions for performance reasons. Let's suppose that all these items have .aspx extension: every time a request to ASP.NET engine would be made we would have to query entire database looking for a key. Then when we would find the key, we would then need to determine what kind of item this is (page, image, file, template...). Finally, we would need to make one more call to database to serve this item.
By having .sflb extension for Images & Documents module, as soon as the request is made we know that it is a content item which should be served as image or downloadable file and therefore Sitefinity can perform much better. This is a common practice with applications that serve content dynamically. The good news, however, is that starting with IIS 7, extensions can be mapped through web.config and this configurations will not be necessary anymore.
As for people on shared hosting, they generally email their hosting providers to map the extensions for them or have this ability in the control panel of their hosting service.
I hope you'll find this information helpful. Let us know if there is anything else we can do for you.
the Telerik team
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