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UpdatePanel controls unavailable - Object reference not set to an instance of an object

I have an UpdatePanel with a Label control, Label1, and a button outside it, Button1, and another Label control outside the UpdatePanel, Label2. When the button is clicked, I want the Label text to be updated in Label1:
ASPX page
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true" AsyncPostBackTimeout="0" />
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
</Triggers>
<asp:ContentTemplate>
<asp:Label ID="Label1" runat="server"></asp:Label>
</asp:ContentTemplate>
</asp:UpdatePanel>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" />
<asp:Label ID="Label2" runat="server"></asp:Label>
</form>
Code-Behind
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
Label2.Text = "some text";
Label1.Text = "some text";
}
This should be straight-forward - I should be able to update the Label1 text with a button click event. The Label2 line succeeds (it obviously won't appear without a page postback, though), where the Label1 line fails with "Object reference is not an instance of an object". Why is Label1 null, when it is right there on the page, just that it is inside an UpdatePanel? How am I supposed to instantiate controls that should already be on the page and accessible, just like Label2 is?

Your async trigger must be inside the update panel. It may not be finding it because it is not inside of the update panel. Furthermore, because you are doing an async postback, only what is inisde of the update panel will get refreshed; thus you are in essence "reseting" Label 1.
This is why your code behind cannot find Label 1. Do this:
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:Label ID="Label1" runat="server"></asp:Label>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" />
<asp:Label ID="Label3" runat="server"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
<asp:Label ID="Label2" runat="server"></asp:Label>
</form>
This will help you to see. The labels 1 and 3 will always get updated now, but since label 2 is outside of the update panel, it will not because the Page doesn't see this on postback.
Code Behind:
protected void Button1_Click(object sender, EventArgs e)
{
Label3.Text = "label 3";
Label2.Text = "label 2";
Label1.Text = "label 1";
}
The result:

Code has <asp:ContentTemplate> and </asp:ContentTemplate> instead of <ContentTemplate> and </ContentTemplate> tags in the UpdatePanel. I corrected this and it works now. The controls became out of scope since the code couldn't find the real ContentTemplate or anything in it.

Dropdown not Updating lbl in Updatepanel

Situation:
Checkbox inside a updatepanel
multiline textbox inside a different updatepanel.
if the user checks the checkbox, the multiline text box gets a name... this works fine.
HTML:
<asp:UpdatePanel ID="upTraveling" runat="server"
UpdateMode="Conditional" ChildrenAsTriggers="False">
<ContentTemplate>
<asp:CheckBox ID="cbRUTraveler" runat="server" Text="I am a Traveler" AutoPostBack="True"
oncheckedchanged="cbRUTraveler_CheckedChanged1" />
</ContentTemplate>
</asp:UpdatePanel>
<td>
<asp:UpdatePanel ID="upTravelers" runat="server" ondatabinding="cbRUTraveler_CheckedChanged1"
UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="tbTravelers"
Class="textwidth" runat="server" TextMode="MultiLine"
placeholder="FName LName, FName LName" required="required">
</asp:TextBox>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger
ControlID="cbRUTraveler" EventName="CheckedChanged" />
</Triggers>
</asp:UpdatePanel>
C#:
protected void cbRUTraveler_CheckedChanged1(object sender, EventArgs e)
{
tbTravelers.Text =
RequesterBPL.RequesterTraveling(cbRUTraveler.Checked, tbTravelers.Text);
going = cbRUTraveler.Checked;
}
I also have 2 other updatepanels on the same page... a dropdown list in one updatepanel and a label in another updatepanel. When a user selects a value in the dropdown list... it's suppose to trigger a name placement in the label.
HTML:
<td>
<asp:UpdatePanel ID="upManager" runat="server"
ondatabinding="ddlTeam_SelectedIndexChanged"
UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="ddlTeam"
EventName="SelectedIndexChanged" />
</Triggers>
<ContentTemplate>
<asp:Label ID="lblManager" runat="server" > </asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</td>
C#:
protected void ddlTeam_SelectedIndexChanged(object sender, EventArgs e)
{
//upManager.Update();
lblManager.Text =
ManagerBPL.ReturnManagerName(ddlTeam.SelectedIndex);
}
However, when a user makes a selection in the dropdown, nothing happens.
until the user checks the checkbox which has nothing to do with the label and the dropdown. Once the user checks (or unchecks) the checkbox... the label gets populated with the selection from the dropdown.
All controls are in a table for structure. I have the scriptmanager in place.
From what I've been reading on the net this maybe a bug... If not a bug does anyone see where I may be going wrong...?
Thanks

Honestly you could do this all Client-Side. A simple example:
$(function () {
$('#<%= drpContent.ClientID %>').blur(function () {
var content = $('#<%= drpContent.ClientID %> option:selected').val();
$('#lblContent').text(content);
}
});
I've provided the initial example with the value declared. The second example is with a text representation.
$(function () {
$('#<%= drpContent.ClientID %>').blur(function () {
var content = $('#<%= drpContent.ClientID %> option:selected').text();
$('#lblContent').text(content);
}
});
An example with a Fiddle. The example though is simple, is far easier then dealing with an Update Panel. That particular control can be a nightmare to deal with, it can be quite painful. Though you asked about the server issue, this option is more viable and more common.
Update Panel (Drawback):
Creates pandomonium between Client / Server Side Events.
Stores your entire page in memory, then recreates (Performance Heavy)
Often breaks Page-State quickly in the Asp.Net Page Life Cycle.
Hopefully this helps.

button OnClick event doesn't fire at the first time in UpdatePanel

I have an issue on button OnClick event.
There is a refresh button in a user control ("header") which will refresh a place holder ("phContent") that generates some other user controls at run time. However, the button OnClick event doesn't fire until the whole place holder content loads.
Page.aspx
<ext:ContentHeader ID="header" runat="server" Visible="false" />
<asp:UpdatePanel ID="upControl" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<asp:PlaceHolder ID="phContent" runat="server"></asp:PlaceHolder>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="header" EventName="OnFormSubmit" />
</Triggers>
</asp:UpdatePanel>
UserControl.ascx
<div>
<asp:Button ID="btnRefresh" runat="server" Text="Refresh" OnClick="btnRefresh_OnClick" />
</div>
UserControl.cs
protected void btnRefresh_OnClick(object sender, EventArgs e)
{
//some code
OnFormSubmit(this, e);
}
public delegate void UserControlFormSubmit(object sender, EventArgs e);
public event UserControlFormSubmit OnFormSubmit;

Not sure what exactly the page and source code is.
But from front-end, take for jQuery as example.
You can try something like:
jQuery(function(){
jQuery('#btnRefresh').on('click',function(){
//load the content by ajax
jQuery('#phContent').load('#chart');
});
});

You have to place the button in updatepanel as well.
<ext:ContentHeader ID="header" runat="server" Visible="false" />
<asp:UpdatePanel ID="upControl" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<asp:Button ID="btnRefresh" runat="server" Text="Refresh" OnClick="btnRefresh_OnClick" />
</ContentTemplate>
</asp:UpdatePanel>

Not able to enable Panel which is outside the update panel from the update panel in asp.net

Here is the scenario,
I have one update panel in which I have radio button.
On check of radio button I want to enable Panel which is outside the update panel.
I have tried following 2 things:
Placing the panel in another update panel didn't work.
Using JavaScript on click of radio button didn't work.

placing the panel in another updatepanel and set update mode as conditional.
You need to do one more thing
On check of radio button event you need to call update method of newly added update panel
UpdatePanel1.Update();

I hope this code sample helps you.
<asp:UpdatePanel ID="udp1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:RadioButton ID="rb1" runat="server" AutoPostBack="true" OnCheckedChanged="Control_CheckedChanged"
Text="Text" GroupName="Group1" />
<asp:RadioButton ID="rb2" runat="server" AutoPostBack="true" OnCheckedChanged="Control_CheckedChanged"
Text="Text2" GroupName="Group1" />
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdatePanel ID="udp2" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Panel ID="pnl1" runat="server" Visible="false">
<asp:Label ID="lblText" runat="server" Text="Text"/>
</asp:Panel>
</ContentTemplate>
<asp:AsyncPostBackTrigger ControlID="rb1" />
<asp:AsyncPostBackTrigger ControlID="rb2" />
</asp:UpdatePanel>
protected void Control_CheckedChanged(object source, EventArgs e)
{
pnl1.Visible=rb1.Checked;
}

Stopping auto page refresh

I use the below code to auto refresh the page every 60 seconds via the AJAX tools in VS2010. Works perfectly.
<asp:MultiView ID="MultiView1" runat="server">
<asp:View ID="View1" runat="server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server" ViewStateMode="Enabled" UpdateMode="Conditional">
<ContentTemplate>
ASP.NET/HTML Code
<p>
<asp:Button ID="Button2" runat="server" Text="Click here" OnClick="Button2_Click" /> to disable the pages automatic refresh.</p>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" />
</Triggers>
</asp:UpdatePanel>
<asp:Timer ID="Timer1" runat="server" Interval="60000">
</asp:Timer>
</asp:View>
<asp:View ID="View2" runat="server">
etc.
</asp:MultiView>
I want to include a button on the asp.net page to cancel the auto refresh.
I tried to include the below but when I clicked the button, it didn't work. The below is the Code Behind for an OnClick event for a Button. The asp.net code is in the above code.
protected void Button2_Click(object sender, EventArgs e)
{
Timer1.Interval = 0;
}
Where am I going wrong? Is this even a way to do this or do I need to go another route in order to allow the user to cancel the auto page refresh?

Thanks to PeterJ I have found the solution. I modified the code and since I clicked it the page has not refreshed. The issue was with my code behind for the button OnClick event. I had:
Timer1.Interval = 0;
When I should have had:
Timer1.Enabled = false;