Hi Tomasz,
Indeed, if the uploaded file exceed the size set to the
maxRequestLength in web.config, then the
RadFileExplorer does not handle the file. The file in this case is handled by the ASP.NET framework only and it disconnects the connection. More details on the subject can be found in
this blog post. As described in the blogpost, the connection with the client's browser is closed automatically by the ASP.NET and this is why that error cannot be handled in order to show a custom message.
I hope this information helps.
Sincerely yours,
Fiko
the Telerik team