Huge file size of another Telerik.Web.UI.WebResource(1).axd

By coincidence we've found out that the webpage size (each page) of the website i'm maintaining has two Telerik.Web.UI.WebResource.axd files. We came across this behaviour when we did a SEO check. So we've downloaded a page to see the file sizes. 

The Telerik.Web.UI.WebResource.axd files:
- Telerik.Web.UI.WebResource.axd = 232kb
- Telerik.Web.UI.WebResource(1).axd = 3294kb

For some reason a second file is being added, which is huge in file size. I've searched the project to find out what's causing this. The only thing that it has, is a RadScriptManager in the Masterpage (which could be the problem maker), where 3 project related scripts are loaded. These scripts are max. 300/400kb in total (this is also huge, but one of them is jQueryUI :)).

So when I delete this RadScriptManager, the page get's EVEN bigger in size with one  more Telerik.Web.UI.WebResource(2).axd file.

I've also defined a scriptsfolder (corresponding to the scripts folder name in the project). This didn't help.

<appsettings>
    <add key="Telerik.Web.UI.ScriptsFolder" value="~/Scripts/;"/>
</appsettings>

Does anybody now what could be causing this issue?

Kind regards

Hi All,

Does anybody know why this occurs and how it can be solved? If it helps I can send specific code.

Thanks!