It was a challenge.

If somebody meets such kind of situation I just want you to know that

This is a problem with iframe loading.

So simple reloading of iframe by means of javascript fix the problem.

 

function ReloadCuteEditorIframe() {

            if (navigator.appName != "Microsoft Internet Explorer") {

                var fr = document.getElementById('<%=CE_HTMLEditor.ClientID %>' + '_Frame'); // CuteEditor ID + addition frame tag

                if (typeof fr.src != "undefined" && fr.src != null)

                { fr.src = fr.src; }

                else window.setTimeout("ReloadCuteEditorIframe()", 1000);

            }

        } 

 

and then you just put this server code where you need to show CuteEditor

 

ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "RefreshIframe", "ReloadCuteEditorIframe();", true);