دلیل خطای Could not load file or assembly در مایگریشن

هنگام باز کردن package manager console و وارد کردن دستور enable-migrations با خطای زیر روبرو میشم .لطفا راهنمایی کنید 

PM> Enable-Migrations
Exception calling "LoadFrom" with "1" argument(s): "Could not load file or assembly 'file:///E:\project\MYCms\packages\EntityFramework.6.4.4\tools\EntityFramework.PowerShell.Utility.dll'
 or one of its dependencies. The system cannot find the file specified."
At E:\project\MYCms\packages\EntityFramework.6.2.0\tools\EntityFramework.psm1:782 char: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 E:\project\MYCms\packages\EntityFramework.6.2.0\tools\EntityFramework.psm1:783 char: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:///E:\project\MYCms\packages\EntityFramework.6.4.4\tools\EntityFramework.PowerShell.dl
l' or one of its dependencies. The system cannot find the file specified."
At E:\project\MYCms\packages\EntityFramework.6.2.0\tools\EntityFramework.psm1:811 char:31
+     $domain.CreateInstanceFrom <<<< (
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException