web app copy grpc DLL build error in Visual Studio when IIS Worker Process is running

Question

After changing some library references in my web app and updating others using nuget, I get errors like the following on this library if the IIS Worker Process is running from a previous debug session:

1>C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(4136,5): error MSB3021: Unable to copy file "C:\JTLanguage\packages\Grpc.Core.2.30.0\runtimes\win\native\grpc_csharp_ext.x86.dll" to "bin\grpc_csharp_ext.x86.dll". The process cannot access the file 'bin\grpc_csharp_ext.x86.dll' because it is being used by another process.

The work-around is to kill the IIS Worker Process each time before I build.

It used to be that I could build and debug repeatedly without doing this. Is there a way to get back to the former behavior?

Curiously, my project doesn't reference this library directly, but a reference to the Grpc.Core library probably brings it in, which itself was a dependency of one of the Google API libraries added automatically.

I'm using Visual Studio 2015 (because it's easier to debug using IE Explorer, and I still have some Silverlight code in it).

Edit: Here's my Web.config, which I updated to have current version numbers. However, it doesn't have an entry for all the libraries. Does it need it?

<?xml version="1.0" encoding="utf-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=301880
  -->
<configuration>
  <configSections>
    
  <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
  <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <connectionStrings>
    <!--
        SQL database not used anymore.
    -->
  </connectionStrings>
  <appSettings>
    <add key="webpages:Version" value="3.0.0.0" />
    <add key="webpages:Enabled" value="false" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
  </appSettings>
  <!--
    For a description of web.config changes see http://go.microsoft.com/fwlink/?LinkId=235367.

    The following attributes can be set on the <httpRuntime> tag.
      <system.Web>
        <httpRuntime targetFramework="4.5.1" />
      </system.Web>
  -->
  <system.web>
    <authentication mode="Windows" />
    <compilation debug="true" targetFramework="4.7.2" />
    <httpRuntime targetFramework="4.7.2" maxRequestLength="20000000" maxQueryStringLength="100000" />
    <globalization culture="en-US" uiCulture="en-US" />
  </system.web>
  <system.web.extensions>
    <scripting>
      <webServices>
        <!-- Update this value to change the value to 
                    a larger value that can accommodate your JSON 
                    strings -->
        <jsonSerialization maxJsonLength="500000000" />
      </webServices>
    </scripting>
  </system.web.extensions>
  <system.webServer>
    <modules>
      <remove name="FormsAuthentication" />
    </modules>
    <security>
      <requestFiltering>
        <requestLimits maxAllowedContentLength="500000000" maxQueryString="100000" />
      </requestFiltering>
    </security>
  </system.webServer>
  <system.net>
    <mailSettings>
      <smtp deliveryMethod="Network" from="xxx">
        <!-- deleted for security -->
      </smtp>
    </mailSettings>
  </system.net>
  <system.serviceModel>
    <services>
      <service name="xxx" behaviorConfiguration="ServiceBehavior">
        <endpoint address="" binding="basicHttpBinding" contract="xxx" />
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
        <!--When hosting a WCF service in IIS, you don't need to specify a base address nor an endpoint, 
          because the Endpoint will simply be the Virtual Path that your service points to.-->
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="ServiceBehavior">
          <!-- To avoid disclosing metadata information, set the value below 
              to false and remove the metadata endpoint above before deployment -->
          <serviceMetadata httpGetEnabled="true" />
          <!-- To receive exception details in faults for debugging purposes, 
              set the value below to true.  Set to false before deployment to 
              avoid disclosing exception information -->
          <serviceDebug includeExceptionDetailInFaults="false" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true" />
    <client>
      <endpoint address="http://api.microsofttranslator.com/V2/soap.svc" binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_LanguageService" contract="TranslatorService.LanguageService" name="BasicHttpBinding_LanguageService" />
    </client>
    <bindings>
      <basicHttpBinding>
        <binding name="xxx" closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard" maxBufferSize="2147483647" maxBufferPoolSize="2147483647" maxReceivedMessageSize="2147483647" messageEncoding="Text" textEncoding="utf-8" transferMode="Buffered" useDefaultWebProxy="true">
          <readerQuotas maxDepth="2147483647" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
          <security mode="None">
            <transport clientCredentialType="None" proxyCredentialType="None" realm="" />
            <message clientCredentialType="UserName" algorithmSuite="Default" />
          </security>
        </binding>
        <binding closeTimeout="00:01:00" openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00" allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard" maxBufferSize="2147483647" maxBufferPoolSize="2147483647" maxReceivedMessageSize="2147483647" messageEncoding="Text" textEncoding="utf-8" transferMode="Buffered" useDefaultWebProxy="true">
          <readerQuotas maxDepth="2147483647" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
          <security mode="None">
            <transport clientCredentialType="None" proxyCredentialType="None" realm="" />
            <message clientCredentialType="UserName" algorithmSuite="Default" />
          </security>
        </binding>
      </basicHttpBinding>
    </bindings>
  </system.serviceModel>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Microsoft.Owin" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Microsoft.Owin.Security.OAuth" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Microsoft.Owin.Security.Cookies" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Microsoft.Owin.Security" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-4.1.0.0" newVersion="4.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" culture="neutral" publicKeyToken="30ad4fe6b2a6aeed" />
        <bindingRedirect oldVersion="0.0.0.0-12.0.0.0" newVersion="12.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-1.6.5135.21930" newVersion="1.6.5135.21930" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="log4net" publicKeyToken="669e0ddf0bb1aa2a" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-2.0.7.0" newVersion="2.0.7.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Interactive.Async" publicKeyToken="94bc3704cddfc263" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.Core" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.0" newVersion="1.45.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.PlatformServices" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.43.0.0" newVersion="1.43.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.0" newVersion="1.45.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.Auth.PlatformServices" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.0" newVersion="1.45.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.Auth" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.0" newVersion="1.45.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.Translate.v2" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.875" newVersion="1.45.0.875" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Api.Gax" publicKeyToken="3ec5ea7f18953e47" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Protobuf" publicKeyToken="a7d26565bac4d604" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.11.4.0" newVersion="3.11.4.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Api.Gax.Grpc" publicKeyToken="3ec5ea7f18953e47" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Api.CommonProtos" publicKeyToken="3ec5ea7f18953e47" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Api.Gax.Rest" publicKeyToken="3ec5ea7f18953e47" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Memory" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.1.1" newVersion="4.0.1.1" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-5.2.7.0" newVersion="5.2.7.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Threading.Tasks.Extensions" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.2.0.1" newVersion="4.2.0.1" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Runtime.CompilerServices.Unsafe" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.6.0" newVersion="4.0.6.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Buffers" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.3.0" newVersion="4.0.3.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Antlr3.Runtime" publicKeyToken="eb42632606e9261f" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.5.0.2" newVersion="3.5.0.2" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Google.Apis.Storage.v1" publicKeyToken="4b01fa6e34db77ab" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.45.0.1964" newVersion="1.45.0.1964" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>
</configuration>

Answer 1

What you could also do is closing Visual Studio and manually delete files in the debug folder of your project. Open your project again and then rebuild/clean solution.

Answer 2

You could try to change the build option(Release). Build your project and go back to Debug mode. If you were in release then the other way.

It will in a way restart the configuration of your project. They are different for Release then Debug .