C# BLToolkit+T4代+MySQL数据库

我收到一个运行T4模板的异常：

Running transformation: System.ArgumentNullException: Value cannot be null.
Parameter name: type
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at Microsoft.VisualStudio.TextTemplatingB9C41E12E53D4F3972EB874C0B96FDFD.GeneratedTextTransformation.GetConnection()
   at Microsoft.VisualStudio.TextTemplatingB9C41E12E53D4F3972EB874C0B96FDFD.GeneratedTextTransformation.LoadServerMetadata()
   at Microsoft.VisualStudio.TextTemplatingB9C41E12E53D4F3972EB874C0B96FDFD.GeneratedTextTransformation.LoadMetadata()
   at Microsoft.VisualStudio.TextTemplatingB9C41E12E53D4F3972EB874C0B96FDFD.GeneratedTextTransformation.GenerateModel()
   at Microsoft.VisualStudio.TextTemplatingB9C41E12E53D4F3972EB874C0B96FDFD.GeneratedTextTransformation.TransformText()
   at Microsoft.VisualStudio.TextTemplating.TransformationRunner.RunTransformation(TemplateProcessingSession session, String source, ITextTemplatingEngineHost host, String& result)

这是我的T4文件：

<#@ template language="C#v3.5"         #>
<#@ output extension=".generated.cs"   #>
<#@ include file="BLToolkit.ttinclude" #>
<#@ include file="MySql.ttinclude"    #>
<#
    ConnectionString     = "Server=localhost;Port=3306;Database=accounting;Uid=root;pwd=1;";
    DataProviderAssembly = @"D:\Temp\BLToolKitMySql\BLToolKitMySql\mysql.data.dll";

    Namespace       = "BLToolKitMySql";
    DataContextName = "DataModel";
    GenerateModel();
#>

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我添加了所有引用，如：BLtoolkit.3、BLtoolkit.Data.DataProvider.MySql3、mysql.Data、sys.Data.linq和MySqlDataProvider.cs，似乎mysql连接无法实例化。 我必须更正MySql.t包含文件：已更改

ConnectionType=MySql.Data.MySqlClient.MySqlConnection，MySql.Data

到

ConnectionType=MySql.Data.MySqlClient.MySqlConnection，MySql.Data

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例外情况是什么？实际代码行是什么？没有关于上述错误的信息。没有文件名，没有项目名，只有第1行和第1列。