Script control is not a registered script control - asp.net

Question

I have a page that uses CustomerDetails.ascx. It uses CM.ascx. Inside CM.ascx I use AJAX Data Controls GridView with ID="gdvRecommendation".
Sometimes when I browse to the page I get the following exception:
Script control 'gdvRecommendation' is not a registered script control. Script controls must be registered using RegisterScriptControl() before calling RegisterScriptDescriptors().
Parameter name: scriptControl
My ScriptManager defined in the master page before the content place holder.
This exception doesn't happened always.
I use CustomerDetails.ascx user controls in other pages and it works great.
Can anyone explain me the problem and what can be the solution?
Edit:
Here is the GridView usage in CM.ascx:
<td valign="top" style="height: 150px;">
<div id="divCMMessage"></div>
<div id='divRecommendation' style="width: 100%; display: inline; overflow: auto;">
<ADC:GridView ID="gdvRecommendation" Width="100%" runat="server" CellSpacing="0" CellPadding="3" HorizontalAlign="Right" ShowHeader="false" RowDataBoundEvent="onRowDataBound_gdvRecommendation">
<RowStyle Height="20px" />
<EmptyDataTemplate>no recommendations</EmptyDataTemplate>
<EmptyDataRowStyle HorizontalAlign="Right" BorderWidth="0" />
<Columns>
<ADC:GridViewImageColumn DataImageUrlField="IndImageUrl" HeaderText="" ItemStyle-Width="25px" ItemStyle-HorizontalAlign="Center"></ADC:GridViewImageColumn>
<ADC:GridViewTemplateColumn HeaderText="">
<ItemTemplate>
<asp:Label ID="TreatName" runat="server" Text=""></asp:Label>
</ItemTemplate>
</ADC:GridViewTemplateColumn>
<ADC:GridViewTemplateColumn HeaderText="">
<ItemTemplate>
<asp:Label ID="TreatType" runat="server" Text=""></asp:Label>
</ItemTemplate>
</ADC:GridViewTemplateColumn>
</Columns>
</ADC:GridView>
</div>
</td>
The CustomerDetails.ascx is inside a MultiView (on MyPage.aspx).

Answer 1

I had a similar problem myself and this post helped me to understand my errors:
==============================================
Script control 'ControlName' is not a registered script control
So you're here because you got the following error.
Script control 'ControlName' is not a registered script control. Script controls must be registered using RegisterScriptControl() before calling RegisterScriptDescriptors().
Parameter name: scriptControl
  
I myself have done a fair bit of googling on this, and there are many
solutions given all over the net. unfortunately these are all very
scenario specific solutions. Some people get their answers, and the
others, like me, don't.
Answer:
You are changing the visibility of a control at the wrong stage of the
page life cycle.
Description:
If you are changing the visibility of a control, you should always do
it during, or before the PreRender event. If you do it after (i.e. in
a End handler of an async task or during PreRenderComplete) you might
run in to this issue.
This is not an issue for simple controls such as buttons or text
boxes. But it will have adverse effects on controls such as grids.
When I say changing the visibility it could be any one of the
following situations
Having visible=false of a control during the early stages of the life cycle and being changed to visible=true during an end handler or PreRenderComplete
Changing the selected view of a MultiView during an end handler or PreRenderComplete
Any other situation where the control may not be visible during the earlier stages of the page life cycle which are set to be visible during the latter stage
 
Reason:
Purely
from my understanding, ASP.NET does not render the scripts or the HTML
related to a control if it is not being shown to the user. The
registering of script controls which is mentioned in the exception
seem to happen during an early stage of the life cycle. if the control
is not visible at this stage, this registration is skipped for that
control. If it's made to be visible at a latter point, you get
yourself a control without some of the relevant scripts.
Anyway this is what I have understood. I may be wrong. But if you come
across this issue, it will definitely help you to check for controls
which are changing visibility at different points of the life cycle.
You will be able to identify your specific problem by doing this and
then come up with a solution on your own.
Hope this information helps some one.
============================
Source

Answer 2

I faced same problem recently, above solution did not work for me. I was Hiding a control and later making it visible in PreRender based on some condition check. Hiding was working fine but when I was making it visible again, it was giving me the same error.
below is What worked for me is-
ScriptManager sm = ScriptManager.GetCurrent(Page);
sm.RegisterScriptControl(control_name);
Then making the control visible resolved my issue.
control_name.Visible = true;
Hopefully it may help someone facing this issue.

Answer 3

I had a similar issue with AJAX, and amusingly it occured only when in 'Debug' mode. In release mode, everything works fine. I have not reached to a conclusion on it yet.
You may want to give it a shot.

Answer 4

In case of a RadAjaxPanel and loading UserControls, reading the answer from jhfelectric, I came up with the following solution (simple one):
Disable AJAX on load (Me.EnableAJAX = False) and Enable it on PreRender. Because PreRender isnot called when removing a control, and is called after adding a control.

Answer 5

You can get this Exception when you have a RadAjaxManager in a user control that itself is also inside a RadAjaxManager, either directly or as the child of another user control.