ef添加迁移出错

Question

ef添加迁移出错

nou*_*med 14 entity-framework ef-migrations asp.net-mvc-5

我有几个类文件.但是现在我添加了新的模型类并尝试键入add-migration InitialCreate.但是我收到以下错误.

PM> add-migration InitialCreate
Exception calling "LoadFrom" with "1" argument(s): "Could not load file or assembly 'file:///C:\Users\user\Documents\Visual Studio 2013\Pro
jects\DigitalHealthWebPrev\packages\EntityFramework.6.1.3\tools\EntityFramework.PowerShell.Utility.dll' or one of its dependencies. Operati
on is not supported. (Exception from HRESULT: 0x80131515)"
At C:\Users\user\Documents\Visual Studio 2013\Projects\DigitalHealthWebPrev\packages\EntityFramework.6.1.3\tools\EntityFramework.psm1:780 c
har:62
+     $utilityAssembly = [System.Reflection.Assembly]::LoadFrom <<<< ((Join-Path $ToolsPath EntityFramework.PowerShell.Utility.dll))
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

You cannot call a method on a null-valued expression.
At C:\Users\user\Documents\Visual Studio 2013\Projects\DigitalHealthWebPrev\packages\EntityFramework.6.1.3\tools\EntityFramework.psm1:781 c
har:50
+     $dispatcher = $utilityAssembly.CreateInstance <<<< (
    + CategoryInfo          : InvalidOperation: (CreateInstance:String) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

Exception calling "CreateInstanceFrom" with "8" argument(s): "Could not load file or assembly 'file:///C:\Users\user\Documents\Visual Studi
o 2013\Projects\DigitalHealthWebPrev\packages\EntityFramework.6.1.3\tools\EntityFramework.PowerShell.dll' or one of its dependencies. Opera
tion is not supported. (Exception from HRESULT: 0x80131515)"
At C:\Users\user\Documents\Visual Studio 2013\Projects\DigitalHealthWebPrev\packages\EntityFramework.6.1.3\tools\EntityFramework.psm1:809 c
har:31
+     $domain.CreateInstanceFrom <<<< (
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

PM>

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