Sys.WebForms.PageRequestManager null or not an object

[Jeff Reinhardt]

I have a radlistbox on a page and when the page loads I get this javascript error:

Sys.WebForms.PageRequestManager is null or not an object


Here is the page code:

<

 

telerik:RadScriptManager ID="RadScriptManager1" runat="server" />

 

<

 

telerik:RadAjaxPanel runat="server" ID="RadAjaxPanel1">

 

Player Name:

&nbsp;<telerik:RadTextBox ID="radtxtAddPlayer" MaxLength="110" runat="server" /><asp:Button ID="btnAddPlayer" OnClick="btnAddPlayer_Click" Text="Add Player" runat="server" />

 

<

 

telerik:RadListBox ID="radlstPlayerPosition"

 

 

runat="server" height="300px" width="150px"

 

 

DataTextField="PlayerName" DataValueField="nPlayerID" AllowDelete="true"

 

 

AllowReorder="true" AllowTransfer="false" AutoPostBack="True">

 

 

</telerik:RadListBox>

 

 

 

 

</

 

telerik:RadAjaxPanel>

Any ideas why I would get this error?   adding a player works even with the error there???

 

[Veselin Vasilev]

Hi Jeff Reinhardt,

The code looks ok and does not throw an exception on my tests. Probably the problem is somewhere else.
If you place that code in a blank new web site - it will work.


Greetings,
Veselin Vasilev
the Telerik team

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