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<add extension=".edmx" type="System.Data.Entity.Design.AspNet.EntityDesignerBuildProvider" />

this is the Assembly of my System Web.config file

Uwe Keim
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Ahtesham
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2 Answers2

51

Open your web.config and add this line below in the Assemblies section:

<add assembly="System.Data.Entity.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />

For more information, check this link:

http://forums.asp.net/t/1698282.aspx

Hope this helps

askrich
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wandos
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24

Adding to @wandos answer, here is the layout for web.config:

<system.web>
  <compilation debug="true" targetFramework="4.5">
    <assemblies>
      <add assembly="System.Data.Entity.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
    </assemblies>
  </compilation>
  <httpRuntime targetFramework="4.5" />
</system.web>
Uwe Keim
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GregoryBrad
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