Install Docker on Windows Server 2016 and bypass SHA256 hash validation error

Installing Windows Container is quite straightforward (follow … except when you have an error message on certain VM (not on every VM) like “Cannot verify the file SHA256. Deleting the file”. After a deep crawl of the web to find a correct way to solve this issue, I found a tons of Github issue answers and blog post that works sometimes but mostly are inaccurate and the package version mentioned is outdated. So I introduce you a method that will keep the process right on board version after version.

Update (07/10/2018) : current version is now 18.03.1-ee-2 (=>

Update (07/16/2018) : Microsoft is playing with manifest (labelling latest binaries as 'TEST'), so files and SHA256 file hash changed over the night. Some installation issues seems better to handle. Stay tuned.

The quick start page from Microsoft to install Docker on Windows Server 2016 is here, and it’s well written (although not very useful when having installation error) :

Get the right version and Docker install file

To download the correct version of the package, you’ll have to get the manifest and to look for your version to get the right URL :

  1. Download the manifest file containing every package version : Start-BitsTransfer -Source
  2. In the manifest, copy the right URL to the install ZIP file (in my case I need 17.06.0-ce) :



Once you know what you need (in my case version 17-06-0-ce), follow these steps to make it work :

  • Go to the temp folder where everything happen (don’t forget to replace by your current username) : cd C:\Users\<username>\AppData\Local\Temp\DockerMsftProvider\
  • Download Docker package (don’t forget to replace the URL by the one you copy previously) : Start-BitsTransfer -Source -Destination /
  • Copy the file to keep a backup (during the process the file is deleted, you won’t have to download it again) : cp
  • Check the SHA256 Hash : Get-FileHash -Path / -Algorithm SHA256
  • Install Docker package : Install-Package -Name docker -ProviderName DockerMsftProvider -Verbose -RequiredVersion 17.06.0-ce
  • Tada ! Things should be OK, so the final step is to restart the computer to make everything work like a charm : Restart-Computer -Force

La GED et la collaboration avec SharePoint – Petit Déjeuner numérique MEDEF NC

Avec l’enjeu de la transition digitale et de l’amélioration de la compétitivité des entreprises locales, la GED et la collaboration documentaire n’ont jamais été aussi importantes à mettre en place.

Allez vers le “sans-papier” est également un enjeu de taille pour les entreprises : économie, écologie et productivité des collaborateurs et des partenaires seront au rendez-vous. Alors pourquoi s’en priver ?

Dans le cadre des Petit-déjeuners du MEDEF-NC, en collaboration avec Sylver SCHORGEN (nouveau MVP sur le territoire depuis peu), nous avons eu l’occasion de présenter aux entreprises locales les fonctionnalités de SharePoint/O365 dans le domaine de la gestion de contenu et de la GED.

Si vous souhaitez vous remémorer les slides du support, les voici à disposition :

Le premier Afterworks MS à Koné

La première édition des Afterworks MS en Province Nord se sont déroulés à Koné ce Lundi 07/08. Devant l'engouement des personnes présentes pour ce type d’événement, les Afterworks sur Koné devraient être réitérer avec un contenu plus spécifique (et moins dense) dans une prochaine édition.

Un grand merci à la CCI de Koné pour le prêt de la salle (et pour nous avoir attendu en fin de journée) et pour accompagner ces initiatives communautaires depuis maintenant plus d’un an.

Comme convenu, nous avons pu partager notre expérience et expertise des technologies Office 365, SharePoint 2016, Visual Studio & .NET, Docker et Windows Container.
Si vous avez des questions sur ces technologies, si vous souhaitez savoir comment nous les déployons chez nos clients ou dans nos sociétés, n'hésitez pas à nous contacter.

Speakers : Sylver Schorgen (SF2i) et Julien Chable (NC IT - MVP Office Server et Development)

Les slides des sessions sont disponibles ci-dessous :
• Office 365 :
• Nano Server :…/prsentation-nano-server-ms-afte…
• SharePoint 2016 :…/prsentation-sharepoint-2016-786…
• Visual Studio et .NET Core :…/visual-studio-2017-launch-keyn…
• Docker :

Image may contain: one or more people, people sitting, table, living room and indoor

Tool of the week : Camtasia from Techsmith

When you are doing conferences and presentations to other people, you need a great tool to capture your screens and voice. I tried a lot of softwares, most of them are free and/or open source but no one give me exactly what I was looking for : a light footprint when operating screen capture (it’s a mess when your system slow down just cause you are screencasting), powerful in terms of features and options to capture your work, with a real editor and bug free (not crashing during working and wasting your time) ! I' don’t have a big expectation but a lots of softwares just deceive me, that’s why I wasn’t able to share my presentations from the last Docker meetup.

Being an MVP is a cool thing : you can share with a lot of people, sharing your tools and knowledges. During a conversation with a buddy of mine, he recommends me the ONE tool you need for your next presentations ! From years now, Techsmith is providing Camtasia to professionals and I decided to try it ! I can just truely recommend you to give it a try here : and share your next presentations.

Share your passion with Camtasia !

Maven Docker build failed with ‘org.apache.http.conn.HttpHostConnectException: Connect to localhost:2375’ on Windows

You can have this kind of error when building a project with Maven and the Docker plugin (by Spotify) :

[INFO] Building image kelios-solutions/annuaire
[INFO] ------------------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 03:16 min
[INFO] Finished at: 2017-06-29T16:59:30+11:00
[INFO] Final Memory: 32M/78M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal com.spotify:docker-maven-plugin:1.0.0:build (default-cli) on project annuaire: Exception caught: java.util.concurrent.ExecutionException:
rs.ProcessingException: org.apache.http.conn.HttpHostConnectException: Connect to localhost:2375 [localhost/, localhost/0:0:0:0:0:0:0:1] failed: Connection refused: connect -> [Help 1]


On Windows, with Docker for Windows, just check if you have exposed the daemon on port 2375 (in Docker for Windows settings) :


And your Maven build should create the Docker image.

Fail to pull Windows Core/Nano Server container images with Docker for Windows ‘unknown blob’

During my last session preparation, I switched Docker for Windows to use Windows containers, to be honest I don’t have use it for some times (my nested virtualized Windows Server 2016 do the job) and I had the following error when downloading the microsoft/nanoserver image : unknow blob


The issue may be that your Docker for Windows daemon is not completely switch to Windows container. So execute the following line to switch it : & ‘C:\Program Files\Docker\Docker\DockerCli.exe’ –SwitchDaemon

Then pull your image again and things should work :


Fail to run a new ASP.NET Core solution with Docker in Visual Studio 2017

Sometimes you want to make a demo to a good friend of you about Docker support in Visual Studio 2017. So your start Visual Studio 2017, create a blank ASP.NET Core (Docker support enabled), press F5 to run the application but things are not really happening like your want. In my case, I had the following message :

The specified framework 'Microsoft.NETCore.App', version '1.1.2' was not found.
  - Check application dependencies and target a framework version installed at:
  - The following versions are installed:
  - Alternatively, install the framework version '1.1.2'.

The issue comes from the fact that Visual Studio 2017 builds a project based on .NET Core 1.1.2 but your Docker image only supports .NET Core 1.1.1 '(see message). Why your image doesn’t support 1.1.2 ? Maybe simply because your image is outdated with no support for 1.1.2. So the trick is quite easy and it consists to execute the pull again the image to force Docker to update the base image :

docker pull microsoft/aspnetcore:1.1

This should solve your issue after several minutes of downloading the updated image layer.

Docker ASP.NET MVC image creation issue ‘GetFileAttributesEx : The system cannot find the path specified’

When using Visual Studio 2017 and trying to create a Docker image for your ASP.NET web app from the standard microsoft\aspnet image (or another image), you may have the following error message : GetFileAttributesEx bin\Release\PublishOutput : The system cannot find the path specified


This error is caused by the .dockerignore file generated by Visual Studio 2017 (more information on .dockerignore file :

How to solve the issue

  1. Open and edit the .dockerignore file located at the root of your Visual Studio project
  2. Remove the first line with the ‘*’ (this is the guilty line !)
  3. Save the modified .dockerignore file
  4. Re execute your docker build command (ex : docker build –t <your tag> .)

Original Visual Studio 2017 .dockerignore file :


The corrected .dockerignore file :


Check your web app to know if everything works fine

  1. First, you won’t be able to use the URL http://localhost, you need the IP address of the container. To find it, execute this command in Powershell :
  2. docker inspect -f "{{ .NetworkSettings.Networks.nat.IPAddress }}" ncit_liasse

  3. Open your favorite browser and enter the URL http//<your ip address> to show you web app shining


More documentation on the use of this image at

Useful documentation on how to migrate an ASP.NET MVC application to Docker :

Now enjoy migrating your ASP.NET MVC web apps to Docker containers !

Lancement de Visual Studio 2017 aux Afterworks@Noumea du 15 Mars

Pour le lancement de Visual Studio 2017 et les 20 ans de l’outil de prédilection de tous les développeurs .NET, il aura bien fallut un évènement spécial des Afterworks@Noumea des communautés MS.

Après une présentation d’un peu plus d’une heure ponctuée de démos sur l’outil et sur les différentes fonctionnalités, .NET Core, l’architecture en microservice avec Docker et la mobilité, nous avons pu enfin goûter au gâteau d’anniversaire :


Retrouvez les slides de la session ici :

Au niveau des ressources sur .NET, n’hésitez pas à me suivre sur LinkedIn (

Encore un grand merci à la CCI de Nouméa pour le prêt des locaux et leur temps.

Bonne journée