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I have both GalaSoft.MvvmLight.Extras.WPF4 and GalaSoft.MvvmLight.WPF4 referenced in my project, however if I declare the following namespace (which does not appear in the drop down list - neither do)

 xmlns:Command="clr-namespace:GalaSoft.MvvmLight.Command; assembly=GalaSoft.MvvmLight.Extras.WPF4"

I get the following error

Error 1 Unable to load the metadata for assembly 'GalaSoft.MvvmLight.Extras.WPF4'. This assembly may have been downloaded from the web. See http://go.microsoft.com/fwlink/?LinkId=179545. The following error was encountered during load: Could not load file or assembly 'GalaSoft.MvvmLight.Extras.WPF4, Version=, Culture=neutral, PublicKeyToken=e80d33351f9dc0a2' or one of its dependencies. The system cannot find the file specified.

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1 Answer 1

up vote 0 down vote accepted

You downloaded the DLL from the web, and so it is marked (via NTFS alternate data streams) as such. Executables and other binaries are blocked by the system automatically in this case.

You need to unlock the file. Assuming you got it from a legit source (I'd assume not) you simply right-click on the DLL and click the "Unblock" button at the bottom of the form.

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They are from a legitimate source, however, they did need to unlocked –  Darren Rockett Jun 2 at 15:19

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