Multiple versions of Microsoft.Web.Administration.dll in IIS 10

On some Windows 10 machine with IIS 10 installed I have three Microsoft.Web.Administration.dll:

Two versions and in GAC (C:\Windows\assembly\GAC_MSIL\Microsoft.Web.Administration\) in and folders respectively and one version in C:\Windows\System32\inetsrv\.

The following XML element in a Visual Studio project file adds a reference to version of Microsoft.Web.Administration.dll:

<Reference Include="Microsoft.Web.Administration, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">

The same XML element with SpecificVersion=False will automatically reference the highest available version on this machine that is

Probably version of Microsoft.Web.Administration.dll is installed with some Windows 10 update, so an application referencing (and probably having a local copy of) version will not work on a clean Windows 10 installation with no updates installed.

To determine the version of Microsoft.Web.Administration.dll I used the following command in PowerShell (it works only with full path):


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