@@ -3,6 +3,8 @@ package main

 import (

 	"fmt"

 	"os"

+	"path/filepath"

+	"runtime"

 	"github.com/Sirupsen/logrus"

 	"github.com/docker/docker/cli"

@@ -61,6 +63,11 @@ func runDaemon(opts daemonOptions) error {

 	daemonCli := NewDaemonCli()

+	// On Windows, if there's no explicit pidfile set, set to under the daemon root

+	if runtime.GOOS == "windows" && opts.daemonConfig.Pidfile == "" {

+		opts.daemonConfig.Pidfile = filepath.Join(opts.daemonConfig.Root, "docker.pid")

+	}

+

 	// On Windows, this may be launching as a service or with an option to

 	// register the service.

 	stop, err := initService(daemonCli)

@@ -2,14 +2,15 @@ package daemon

 import (

 	"os"

+	"path/filepath"

 	"github.com/docker/docker/api/types"

 	"github.com/spf13/pflag"

 )

 var (

-	defaultPidFile = os.Getenv("programdata") + string(os.PathSeparator) + "docker.pid"

-	defaultGraph   = os.Getenv("programdata") + string(os.PathSeparator) + "docker"

+	defaultPidFile string

+	defaultGraph   = filepath.Join(os.Getenv("programdata"), "docker")

 )

 // bridgeConfig stores all the bridge driver specific