Windows container failed to start with error, "failed to create endpoint on network nat: HNS failed with error : Failed to create endpoint."

After searching around I stunbled upon this issue on github. This seemed to be a known issue with Windows containers on Windows server TP5.

Then thanks to this forum, I found the solution You can check active static port mapping with below command

C:\>powershell
PS C:\>Get-NetNatStaticMapping


StaticMappingID               : 3
NatName                       : Hda6caca4-06ec-4251-8a98-1fe0b4c5af88
Protocol                      : TCP
RemoteExternalIPAddressPrefix : 0.0.0.0/0
ExternalIPAddress             : 0.0.0.0
ExternalPort                  : 80
InternalIPAddress             : 172.31.181.4
InternalPort                  : 80
InternalRoutingDomainId       : {00000000-0000-0000-0000-000000000000}
Active                        : True

From above output it seemed that even though container was removed the static port mapping was not removed and was still active.

But I removed it with below command.

PS C:\> Get-NetNatStaticMapping | ? ExternalPort -eq 80 | Remove-NetNatStaticMapping

Then simply rebooted the system and the error was gone.

For me these steps solved the problem:

Stop-Service docker
Get-ContainerNetwork | Remove-ContainerNetwork
Get-NetNat | Remove-NetNat
Get-VMSwitch | Remove-VMSwitch
Start-Service docker

(suggested by JMesser81 at:https://github.com/Microsoft/Virtualization-Documentation/issues/273)

I had similar error.

$ docker --version
Docker version 1.13.0-rc3, build 4d92237
$ docker-compose -f .\docker-compose.windows.yml up
Starting musicstore_db_1

ERROR: for db  Cannot start service db: {"message":"failed to create endpoint musicstore_db_1 on network nat: HNS failed with error : Unspecified error"}
ERROR: Encountered errors while bringing up the project.

Static mapping removal did not work, only network removal helped:

Get-ContainerNetwork -Name nat | Remove-ContainerNetwork

Execute the command in PowerShell as administrator, then restart Docker.

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Update:

Use CleanupContainerHostNetworking.ps1 script to resolve Docker 17 networking issues.

.\CleanupContainerHostNetworking.ps1 -Cleanup -ForceDeleteAllSwitches