Weird VS2010 error with silverlight

BrianMulcahy

WHen trying to compile and run a program from my desktop I get These errors.

Error 1 The tag 'ToggleLayerAction' does not exist in XML namespace 'http://schemas.esri.com/arcgis/client/2009'. 
Error 4 A value of type 'ToggleLayerAction' cannot be added to a collection or dictionary of type 'TriggerActionCollection'.

If I run the program and compile it when it is on my flashdrive I do not receive these errors.

Here is the code in question

<UserControl xmlns:toolkit="http://schemas.microsoft.com/winfx/2006/xaml/presentation/toolkit"  x:Class="RTLA_Silverlight.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
    xmlns:esri="http://schemas.esri.com/arcgis/client/2009"
    xmlns:esriExtensibility="http://schemas.esri.com/arcgis/client/extensibility/2010"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
 mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="600" 
 xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
    xmlns:ei="clr-namespace:Microsoft.Expression.Interactivity.Core;assembly=Microsoft.Expression.Interactions"
    xmlns:userControls="clr-namespace:ESRI.ArcGIS.SilverlightMapApp"
    xmlns:actions="clr-namespace:ESRI.ArcGIS.SilverlightMapApp.Actions"
    >


<CheckBox Content="Landsat5 TM" 
            ToolTipService.ToolTip="Landsat5TM"
                                                                          ClickMode="Press" >
                                                                    <i:Interaction.Triggers>
                                                                        <i:EventTrigger EventName="Click">
                                                                            <esri:ToggleLayerAction LayerID="Landsat5TM" 
                                                                                                    TargetName="Map"/>
                                                                        </i:EventTrigger>
                                                                    </i:Interaction.Triggers>
                                                                </CheckBox>

Obviously not all the code but this is what throws the error.

Another thing is it just started randomly without changing the code.