Error:Extender controls may not be registered before PreRender

I have a user control in which I use an autocomplete extender for a textbox.in code behind I register a script in OnPreRender method.I used this user control in 2 pages.In one of them it works well but in another page with the same structure I get this error "Extender controls may not be registered before PreRender".

Does anybody know what it is?

here is the user controls code:

<%@dotnet.itags.org.ControlLanguage="C#"AutoEventWireup="true"CodeFile="AddSignaturePanel.ascx.cs"Inherits="AddSignaturePanel" %>

<%@dotnet.itags.org.RegisterAssembly="Microsoft.Web.Preview"Namespace="Microsoft.Web.Preview.UI.Controls"TagPrefix="asp" %>

<

asp:ButtonID="btnDivOpener"CssClass="Button"runat="server"meta:resourcekey="btnDivOpenerResource"/>

<divdir="rtl"id='PersonDiv'style=' visibility:hidden; border:1px solid #000080; position: absolute; width: 250px;background-color: #e8f1d6;'><tablewidth='100%'><tr><tdclass="TwoColTDLabelDiv"><asp:LabelCssClass="TwoColLabel"ID="lblUserName"runat="server"meta:resourcekey="lblUserNameResource"></asp:Label></td><tdclass="TwoColTDSeperatorDiv"></td><tdclass="TwoColTDControlDiv"><asp:TextBoxCssClass="SigPanelTextBox"ID="txtUserName"runat="server"meta:resourcekey="txtUserNameResource1"></asp:TextBox><asp:AutoCompleteExtenderID="NameAutoComplete"Visible="true"runat="server"TargetControlID="txtUserName"MinimumPrefixLength="1"ServiceMethod="GetUserByUsername"ServicePath="../../Common/Services/PersonSearchSRVC.asmx"/></td></tr><tr><tdclass="TwoColTDLabelDiv"><asp:LabelCssClass="TwoColLabel"ID="lblSignatureKey"runat="server"meta:resourcekey="lblSignatureKeyResource"></asp:Label></td><tdclass="TwoColTDSeperatorDiv"></td><tdclass="TwoColTDControlDiv"><asp:TextBoxCssClass="SigPanelTextBox"ID="txtSignatureKey"runat="server"meta:resourcekey="txtSignatureKeyResource1"></asp:TextBox></td></tr><tr><tdclass="TwoColTDLabelDiv"><asp:LabelID="lblCondition"runat="server"CssClass="TwoColLabel"meta:resourcekey="lblConditionResource"></asp:Label></td><tdclass="TwoColTDSeperatorDiv"></td><tdclass="TwoColTDControlDiv"><asp:TextBoxID="txtCondition"runat="server"CssClass="SigPanelTextBox"meta:resourcekey="txtConditionResource1"></asp:TextBox></td></tr><tr><tdclass="TwoColTDLabelDiv"><asp:LabelID="lblComment"runat="server"CssClass="TwoColLabel"meta:resourcekey="lblCommentResource"></asp:Label></td><tdclass="TwoColTDSeperatorDiv"></td><tdclass="TwoColTDControlDiv"><asp:TextBoxID="txaComment"runat="server"CssClass="SigPanelTextBox"TextMode="MultiLine"meta:resourcekey="txaCommentResource1"></asp:TextBox></td></tr><tr><tdclass="DivButtonTDButtons"colspan="3"><asp:ButtonCssClass="Button"ID="btnSubmit"runat="server"meta:resourcekey="btnSubmitResource"/><asp:ButtonCssClass="Button"ID="btnUnSubmit"runat="server"meta:resourcekey="btnUnSubmitResource"/><asp:ButtonCssClass="Button"ID="btnCancel"runat="server"meta:resourcekey="btnCancelResource"/> </td></tr></table></div>

and in code behind I have this:

public

partialclassAddSignaturePanel :ModuleBase

{

#region

private membersprivateIEntity _entity;

#endregion

#region

Public PropertiespublicIEntity Entity

{

set

{

base.ViewState["Type"] = ((IEntity)value).Type ;base.ViewState["Key"] = ((IEntity)value).Key;

}

//get//{// return (IEntity)base.ViewState["Type&Key"];//}

}

#endregion

#region

Delegates and EventHandlerspubliceventAddSignatureEventHandler SubmitEvent;publiceventAddSignatureEventHandler UnSubmitEvent;publicvirtualvoid OnSubmit(object sender,EventArgs e)

{

string userName = txtUserName.Text;string signatureKey = txtSignatureKey.Text;string comment = txaComment.Text;try

{

User user =SecurityService.Instance.GetUser(userName);EntityReference er= Faraconesh.ApplicationFramework.Core.DataAccess.EntityReferenceDAS.Instance.GetEntityReference(base.ViewState["Key"].ToString(),base.ViewState["Type"].ToString());Signature sign =SignatureService.Instance.AddSignature(user.Person, signatureKey, er,"", comment);AddSignatureEventArgs ase =newAddSignatureEventArgs();

ase.Signature = sign;

if (sign !=null && SubmitEvent !=null)

{

SubmitEvent(

this, ase);

}

}

catch (Exception ex)

{

thrownewException(ex.Message);

}

}

publicvirtualvoid OnUnSubmit(object sender,EventArgs e)

{

string userName = txtUserName.Text;string signatureKey = txtSignatureKey.Text;string comment = txaComment.Text;User user =SecurityService.Instance.GetUser(userName);Signature sign =SignatureService.Instance.AddSignature(user.Person, signatureKey, (IEntity)user,"", comment);AddSignatureEventArgs ase =newAddSignatureEventArgs();

ase.Signature = sign;

if (sign !=null && UnSubmitEvent !=null)

{

UnSubmitEvent(

this, ase);

}

}

#endregion

#region

overridden methodsprotectedvoid Page_Load(object sender,EventArgs e)

{

btnUnSubmit.Click +=

newEventHandler(OnUnSubmit);

btnSubmit.Click +=

newEventHandler(OnSubmit);

btnDivOpener.Attributes.Add(

"onClick","openSearchDiv" +this.ClientID +"();return false;");

btnCancel.Attributes.Add(

"onClick","closeSearchDiv" +this.ClientID +"();return false;");

}

protectedoverridevoid OnPreRender(EventArgs e)

{

base.OnPreRender(e);if (!Page.ClientScript.IsClientScriptBlockRegistered("DivOpener" +this.ClientID))

{

StringBuilder strBuilder =newStringBuilder();

strBuilder.Append(

"<script type='text/javascript'>");

strBuilder.Append(

"function openSearchDiv" +this.ClientID +"(){");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

" document.getElementById('PersonDiv').style.visibility='visible';");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

" document.getElementById('PersonDiv').style.top= screen.availWidth/2 -250;");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

" document.getElementById('PersonDiv').style.left=screen.availHeight/2;");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

"}");

strBuilder.Append(

"function closeSearchDiv" +this.ClientID +"(){");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

" document.getElementById('PersonDiv').style.visibility='hidden';");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

"}");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

"</script>");

strBuilder.Append(

Environment.NewLine);string script = strBuilder.ToString();

Page.ClientScript.RegisterClientScriptBlock(

typeof(AddSignaturePanel),"DivOpener" +this.ClientID, script);

}

if (!Page.ClientScript.IsStartupScriptRegistered("ShowModalDialog" +this.ClientID))

{

StringBuilder strBuilder =newStringBuilder();

strBuilder.Append(

"<script type='text/javascript'>");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

"var PersonPopup"+this.ClientID+"= new modalDialog('PersonDiv',50,50);");

strBuilder.Append(

Environment.NewLine);

strBuilder.Append(

"</script>");

strBuilder.Append(

Environment.NewLine);string script=strBuilder.ToString();

Page.ClientScript.RegisterStartupScript(

typeof(AddSignaturePanel),"ShowModalDialog" +this.ClientID, script);

}

}

#endregion

publicUser GetUser()

{

string userName=txtUserName.Text;string signatureKey = txtSignatureKey.Text;string comment=txaComment.Text;User user=SecurityService.Instance.GetUser(userName);return user;

}

}

I found the solution.just in the aspx file in which I used the user control I'd overridden onprerender method but didnt call tha base prerender for it.

Hi...

If u want to get ride of this error then

<asp:ScriptManagerID="ScriptManager1"runat="server"/>

if u r using usercontrol then paste this in ur .aspx page...