docker build - "error during connect: This error may indicate that the docker daemon is not running."

Question

I'm working on Windows 10 with the CLIs Git Bash, WSL2 and PowerShell. So far, I have not figured out how to make the command docker build -t aws/codebuild/standard:3.0 . work.

I've already tried several things:

1. In Git Bash: net stop docker
2. Opening PowerShell in Admin-mode, restarting Docker Daemon via cd "C:\Program Files\Docker\Docker" && ./DockerCli.exe -SwitchDaemon
3. Starting dockerd with admin rights on WSL2 - shell
4. Start "Docker Desktop" on Windows 10 manually until it states "Docker Service not running" (click on "start", "net" window opens and closes immediately, and nothing further happens):

Some more specifics on CLI outputs related to Option 1:

user@hd1pcms0347 MINGW64 ~/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0 (master)
$ net stop docker
The service name is invalid.

More help is available by typing NET HELPMSG 2185.


user@hd1pcms0347 MINGW64 ~/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0 (master)
$ net stop com.docker.service
The Docker Desktop Service service is not started.

More help is available by typing NET HELPMSG 3521.


user@hd1pcms0347 MINGW64 ~/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0 (master)
$ net start docker
The service name is invalid.

More help is available by typing NET HELPMSG 2185.


user@hd1pcms0347 MINGW64 ~/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0 (master)
$ net start com.docker.service
System error 5 has occurred.

Access is denied.


user@hd1pcms0347 MINGW64 ~/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0 (master)
$ sudo net start com.docker.service
System error 1058 has occurred.

The service cannot be started, either because it is disabled or because it has no enabled devices associated with it.

Some more specifics on WSL2-shell outputs with dockerd (Option 3):

user@hd1pcms0347:/mnt/c/Users/username/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0$ docker build -t aws/codebuild/standard:3.0 .
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

user@hd1pcms0347:/mnt/c/Users/username/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0$ sudo dockerd
[sudo] password for user: 
INFO[2021-06-30T15:04:18.569848200+02:00] Starting up
INFO[2021-06-30T15:04:18.596368100+02:00] libcontainerd: started new containerd process  pid=3612
INFO[2021-06-30T15:04:18.596759700+02:00] parsed scheme: "unix"                         module=grpc
INFO[2021-06-30T15:04:18.597062800+02:00] scheme "unix" not registered, fallback to default scheme  module=grpc
INFO[2021-06-30T15:04:18.597402000+02:00] ccResolverWrapper: sending update to cc: {[{unix:///var/run/docker/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}  module=grpc
INFO[2021-06-30T15:04:18.597708900+02:00] ClientConn switching balancer to "pick_first"  module=grpc
INFO[2021-06-30T15:04:18.642947300+02:00] starting containerd                           revision= version="1.4.4-0ubuntu1~20.04.2"
INFO[2021-06-30T15:04:18.670987400+02:00] loading plugin "io.containerd.content.v1.content"...  type=io.containerd.content.v1
INFO[2021-06-30T15:04:18.673888800+02:00] loading plugin "io.containerd.snapshotter.v1.aufs"...  type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.750046200+02:00] skip loading plugin "io.containerd.snapshotter.v1.aufs"...  error="aufs is not supported (modprobe aufs failed: exit status 1 \"modprobe: FATAL: Module aufs not found in directory /lib/modules/4.4.0-19041-Microsoft\\n\"): skip plugin" type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.750651600+02:00] loading plugin "io.containerd.snapshotter.v1.btrfs"...  type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.751899400+02:00] skip loading plugin "io.containerd.snapshotter.v1.btrfs"...  error="path /var/lib/docker/containerd/daemon/io.containerd.snapshotter.v1.btrfs (wslfs) must be a btrfs filesystem to be used with the btrfs snapshotter: skip plugin" type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.752328200+02:00] loading plugin "io.containerd.snapshotter.v1.devmapper"...  type=io.containerd.snapshotter.v1
WARN[2021-06-30T15:04:18.752652800+02:00] failed to load plugin io.containerd.snapshotter.v1.devmapper  error="devmapper not configured"
INFO[2021-06-30T15:04:18.752973800+02:00] loading plugin "io.containerd.snapshotter.v1.native"...  type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.754531700+02:00] loading plugin "io.containerd.snapshotter.v1.overlayfs"...  type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.759859700+02:00] loading plugin "io.containerd.snapshotter.v1.zfs"...  type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.760367200+02:00] skip loading plugin "io.containerd.snapshotter.v1.zfs"...  error="path /var/lib/docker/containerd/daemon/io.containerd.snapshotter.v1.zfs must be a 
zfs filesystem to be used with the zfs snapshotter: skip plugin" type=io.containerd.snapshotter.v1
INFO[2021-06-30T15:04:18.760925000+02:00] loading plugin "io.containerd.metadata.v1.bolt"...  type=io.containerd.metadata.v1
WARN[2021-06-30T15:04:18.762074700+02:00] could not use snapshotter devmapper in metadata plugin  error="devmapper not configured"
INFO[2021-06-30T15:04:18.762472300+02:00] metadata content store policy set             policy=shared
INFO[2021-06-30T15:04:18.769383900+02:00] loading plugin "io.containerd.differ.v1.walking"...  type=io.containerd.differ.v1
INFO[2021-06-30T15:04:18.769855000+02:00] loading plugin "io.containerd.gc.v1.scheduler"...  type=io.containerd.gc.v1
INFO[2021-06-30T15:04:18.770209900+02:00] loading plugin "io.containerd.service.v1.introspection-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.770586300+02:00] loading plugin "io.containerd.service.v1.containers-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.771021300+02:00] loading plugin "io.containerd.service.v1.content-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.771445400+02:00] loading plugin "io.containerd.service.v1.diff-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.772519100+02:00] loading plugin "io.containerd.service.v1.images-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.773311600+02:00] loading plugin "io.containerd.service.v1.leases-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.773761100+02:00] loading plugin "io.containerd.service.v1.namespaces-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.774170300+02:00] loading plugin "io.containerd.service.v1.snapshots-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.774548800+02:00] loading plugin "io.containerd.runtime.v1.linux"...  type=io.containerd.runtime.v1
INFO[2021-06-30T15:04:18.776950300+02:00] loading plugin "io.containerd.runtime.v2.task"...  type=io.containerd.runtime.v2
INFO[2021-06-30T15:04:18.780732500+02:00] loading plugin "io.containerd.monitor.v1.cgroups"...  type=io.containerd.monitor.v1
INFO[2021-06-30T15:04:18.782998700+02:00] loading plugin "io.containerd.service.v1.tasks-service"...  type=io.containerd.service.v1
INFO[2021-06-30T15:04:18.783405000+02:00] loading plugin "io.containerd.internal.v1.restart"...  type=io.containerd.internal.v1
INFO[2021-06-30T15:04:18.783818900+02:00] loading plugin "io.containerd.grpc.v1.containers"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.784270200+02:00] loading plugin "io.containerd.grpc.v1.content"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.784640600+02:00] loading plugin "io.containerd.grpc.v1.diff"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.784918600+02:00] loading plugin "io.containerd.grpc.v1.events"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.785216200+02:00] loading plugin "io.containerd.grpc.v1.healthcheck"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.785516200+02:00] loading plugin "io.containerd.grpc.v1.images"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.785764200+02:00] loading plugin "io.containerd.grpc.v1.leases"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.786065700+02:00] loading plugin "io.containerd.grpc.v1.namespaces"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.786339300+02:00] loading plugin "io.containerd.internal.v1.opt"...  type=io.containerd.internal.v1
INFO[2021-06-30T15:04:18.790367300+02:00] loading plugin "io.containerd.grpc.v1.snapshots"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.790831300+02:00] loading plugin "io.containerd.grpc.v1.tasks"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.791225900+02:00] loading plugin "io.containerd.grpc.v1.version"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.791812700+02:00] loading plugin "io.containerd.grpc.v1.introspection"...  type=io.containerd.grpc.v1
INFO[2021-06-30T15:04:18.794298100+02:00] serving...                                    address=/var/run/docker/containerd/containerd-debug.sock
INFO[2021-06-30T15:04:18.796248300+02:00] serving...                                    address=/var/run/docker/containerd/containerd.sock.ttrpc
INFO[2021-06-30T15:04:18.797459100+02:00] serving...                                    address=/var/run/docker/containerd/containerd.sock
INFO[2021-06-30T15:04:18.797772600+02:00] containerd successfully booted in 0.160923s
INFO[2021-06-30T15:04:18.826449900+02:00] parsed scheme: "unix"                         module=grpc
INFO[2021-06-30T15:04:18.828408900+02:00] scheme "unix" not registered, fallback to default scheme  module=grpc
INFO[2021-06-30T15:04:18.829324300+02:00] ccResolverWrapper: sending update to cc: {[{unix:///var/run/docker/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}  module=grpc
INFO[2021-06-30T15:04:18.829885000+02:00] ClientConn switching balancer to "pick_first"  module=grpc
INFO[2021-06-30T15:04:18.835378400+02:00] parsed scheme: "unix"                         module=grpc
INFO[2021-06-30T15:04:18.835778100+02:00] scheme "unix" not registered, fallback to default scheme  module=grpc
INFO[2021-06-30T15:04:18.836458600+02:00] ccResolverWrapper: sending update to cc: {[{unix:///var/run/docker/containerd/containerd.sock  <nil> 0 <nil>}] <nil> <nil>}  module=grpc
INFO[2021-06-30T15:04:18.836858700+02:00] ClientConn switching balancer to "pick_first"  module=grpc
WARN[2021-06-30T15:04:18.914129500+02:00] Your kernel does not support cgroup memory limit 
WARN[2021-06-30T15:04:18.914502600+02:00] Unable to find cpu cgroup in mounts
WARN[2021-06-30T15:04:18.914702600+02:00] Unable to find blkio cgroup in mounts
WARN[2021-06-30T15:04:18.914969800+02:00] Unable to find cpuset cgroup in mounts
WARN[2021-06-30T15:04:18.915207100+02:00] Unable to find pids cgroup in mounts
INFO[2021-06-30T15:04:18.915689900+02:00] Loading containers: start.
WARN[2021-06-30T15:04:18.959628600+02:00] Running iptables --wait -t nat -L -n failed with message: `iptables v1.8.4 (legacy): can't initialize iptables table `nat': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.`, error: exit status 3
INFO[2021-06-30T15:04:19.159782300+02:00] stopping event stream following graceful shutdown  error="<nil>" module=libcontainerd namespace=moby
INFO[2021-06-30T15:04:19.161237700+02:00] stopping healthcheck following graceful shutdown  module=libcontainerd
INFO[2021-06-30T15:04:19.161256700+02:00] stopping event stream following graceful shutdown  error="context canceled" module=libcontainerd namespace=plugins.moby
WARN[2021-06-30T15:04:20.171320700+02:00] grpc: addrConn.createTransport failed to connect to {unix:///var/run/docker/containerd/containerd.sock  <nil> 0 <nil>}. Err :connection error: desc 
= "transport: Error while dialing dial unix:///var/run/docker/containerd/containerd.sock: timeout". Reconnecting...  module=grpc
failed to start daemon: Error initializing network controller: error obtaining controller instance: failed to create NAT chain DOCKER: iptables failed: iptables -t nat -N DOCKER: iptables v1.8.4 (legacy): can't initialize iptables table `nat': Table does not exist (do you need to insmod?)
Perhaps iptables or your kernel needs to be upgraded.
 (exit status 3)

user@hd1pcms0347:/mnt/c/Users/username/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0$ docker build -t aws/codebuild/standard:3.0 .
Got permission denied while trying to connect to the Docker daemon socket at unix:///var/run/docker.sock: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.24/build?buildargs=%7B%7D&cachefrom=%5B%5D&cgroupparent=&cpuperiod=0&cpuquota=0&cpusetcpus=&cpusetmems=&cpushares=0&dockerfile=Dockerfile&labels=%7B%7D&memory=0&memswap=0&networkmode=default&rm=1&shmsize=0&t=aws%2Fcodebuild%2Fstandard%3A3.0&target=&ulimits=null&version=1: dial unix /var/run/docker.sock: connect: permission denied

user@hd1pcms0347:/mnt/c/Users/username/Projects/aws-codebuild-docker-images/ubuntu/standard/3.0$ sudo docker build -t aws/codebuild/standard:3.0 .
Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

---

EDIT on 01-07-2021:

I've managed to make docker work again by simply reinstalling it. Yet, I'd be delighted to know if there is any specific reason for the above-mentioned behavior.