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Adding a directory to the PATH environment variable in Windows

I am trying to add C:\xampp\php to my system PATH environment variable in Windows.

I have already added it using the Environment Variables dialog box.

But when I type into my console:

C:\>path

it doesn't show the new C:\xampp\php directory:

PATH=D:\Program Files\Autodesk\Maya2008\bin;C:\Ruby192\bin;C:\WINDOWS\system32;C:\WINDOWS;
C:\WINDOWS\System32\Wbem;C:\PROGRA~1\DISKEE~2\DISKEE~1\;c:\Program Files\Microsoft SQL
Server\90\Tools\binn\;C:\Program Files\QuickTime\QTSystem\;D:\Program Files\TortoiseSVN\bin
;D:\Program Files\Bazaar;C:\Program Files\Android\android-sdk\tools;D:\Program Files\
Microsoft Visual Studio\Common\Tools\WinNT;D:\Program Files\Microsoft Visual Studio\Common
\MSDev98\Bin;D:\Program Files\Microsoft Visual Studio\Common\Tools;D:\Program Files\
Microsoft Visual Studio\VC98\bin

I have two questions:

Why did this happen? Is there something I did wrong? Also, how do I add directories to my PATH variable using the console (and programmatically, with a batch file)?

This is on topic because it's a question about 'tools programmers commonly use'. If you develop on Windows and you've never needed to modify the PATH, I'm surprised. To satiate the desire for being related to programming, I've highlighted what the highest voted answer pointed out: You can do this programmatically through the console (or via a batch file).
thanks for the review @GeorgeStocker well yeah I did it programmatically and but I just haven't had an idea that I need to relogin after applying changes in the console session. (and I think its only in my case) but the highest voted answer generally answers the question
@George - agreed, but as it stands, this question is written for Super User, and not Stack Overflow. Super User will provide help with web server configurations for personal use. Stack Overflow is for programming questions.
Exit and open a new console... If you're using bash, that may require a system reboot before the changes persist, depending on how/what you are using,.

s
srm

Option 1

After you change PATH with the GUI, close and re-open the console window.

This works because only programs started after the change will see the new PATH.

Option 2

This option only affects your current shell session, not the whole system. Execute this command in the command window you have open:

set PATH=%PATH%;C:\your\path\here\

This command appends C:\your\path\here\ to the current PATH. If your path includes spaces, you do NOT need to include quote marks.

Breaking it down:

set – A command that changes cmd's environment variables only for the current cmd session; other programs and the system are unaffected.

PATH= – Signifies that PATH is the environment variable to be temporarily changed.

%PATH%;C:\your\path\here\ – The %PATH% part expands to the current value of PATH, and ;C:\your\path\here\ is then concatenated to it. This becomes the new PATH.


@Ilya: I meant for you to open the console window after the path was changed in MyComputer->Properties->Advanced->Env Variables->Path. Some windows apps will propagate environment variable changes after they're started and some will not. WinXP cmd.exe does not.
if I exit the console and I rerun I have to reset the path. Any idea how to make this change permanent?
@David天宇Wong If you follow "My Computer" > "Properties" > "Advanced" > "Environment Variables" > "Path". and add the directory to the end of that string, it will stay. Just be sure to open console after making the change.
@David天宇Wong Just found "SETX is a way to make persistent changes, like the dialog." so the SETX command should do it
It would be nicer if you add a note that Option 2 is session-wide, not system-wide.
S
StayOnTarget

WARNING: This solution may be destructive to your PATH, and the stability of your system. As a side effect, it will merge your user and system PATH, and truncate PATH to 1024 characters. The effect of this command is irreversible. Make a backup of PATH first. See the comments for more information. Don't blindly copy-and-paste this. Use with caution.

You can permanently add a path to PATH with the setx command:

setx /M path "%path%;C:\your\path\here\"

Remove the /M flag if you want to set the user PATH instead of the system PATH.

Notes:

The setx command is only available in Windows 7 and later.

You should run this command from an elevated command prompt.

If you only want to change it for the current session, use set.


SETX /M path "%path%;C:\Program Files (x86)\Git\bin\" to set PATH value on machine level
Why is this this not the accepted answer? I'd imagine most people would want to set their path permanently...
WARNING : Because of the use of %PATH% variable, this command merge global env variables with users ones. Doesn't it ? This may creates unwanted side effects, especially with the /M switch
WARNING 2: The %PATH% variable may not be in sync with environment variables as it is loaded at the launch of the command prompt and never reloaded afterward (even when executing setx command). Also it could have been changed locally by previously executed scripts.
P
Peter Mortensen

This only modifies the registry. An existing process won't use these values. A new process will do so if it is started after this change and doesn't inherit the old environment from its parent.

You didn't specify how you started the console session. The best way to ensure this is to exit the command shell and run it again. It should then inherit the updated PATH environment variable.


Hmm, no, it truly really only modifies the registry. Ought to be a bit obvious from doing this in a Control Panel dialog instead of, say, the command prompt with the PATH command. You can observe what it does easily with SysInternals' Process Monitor, should you care. Using PATH is not the same, any changes you make will be lost when the console closes. SETX is a way to make persistent changes, like the dialog.
This is correct. You always have to restart your console session before it picks up new environment variables.
Would the console session update the variables if WM_SETTINGCHANGE message was sent from an apllication? stackoverflow.com/a/8358361
It is theoretically possible, no practical CRT implementation I know of actually does this. Explorer does.
Background information corroborating this: blogs.msdn.microsoft.com/oldnewthing/20150915-00/?p=91591
P
Peter Mortensen

You don't need any set or setx command. Simply open the terminal and type:

PATH

This shows the current value of PATH variable. Now you want to add directory to it? Simply type:

PATH %PATH%;C:\xampp\php

If for any reason you want to clear the PATH variable (no paths at all or delete all paths in it), type:

PATH ;

Update

Like Danial Wilson noted in comment below, it sets the path only in the current session. To set the path permanently, use setx but be aware, although that sets the path permanently, but not in the current session, so you have to start a new command line to see the changes. More information is here.

To check if an environmental variable exist or see its value, use the ECHO command:

echo %YOUR_ENV_VARIABLE%

It worked :) how about that! 'PATH %PATH%;' I can remember that
I think this only works for the instance of the cmd session, use setx to change it permanently
Don't include quotes with this. For example call PATH %PATH%;C:\Program Files\... instead of PATH "%PATH%;C:\Program Files\..."
Don't use setx! You risk truncation of your path variable, losing many other paths you spent time setting. Heed warnings above.
@STWilson, too late to see your comment!
M
Mariano Desanze

I would use PowerShell instead!

To add a directory to PATH using PowerShell, do the following:

$PATH = [Environment]::GetEnvironmentVariable("PATH")
$xampp_path = "C:\xampp\php"
[Environment]::SetEnvironmentVariable("PATH", "$PATH;$xampp_path")

To set the variable for all users, machine-wide, the last line should be like:

[Environment]::SetEnvironmentVariable("PATH", "$PATH;$xampp_path", "Machine")

In a PowerShell script, you might want to check for the presence of your C:\xampp\php before adding to PATH (in case it has been previously added). You can wrap it in an if conditional.

So putting it all together:

$PATH = [Environment]::GetEnvironmentVariable("PATH", "Machine")
$xampp_path = "C:\xampp\php"
if( $PATH -notlike "*"+$xampp_path+"*" ){
    [Environment]::SetEnvironmentVariable("PATH", "$PATH;$xampp_path", "Machine")
}

Better still, one could create a generic function. Just supply the directory you wish to add:

function AddTo-Path{
param(
    [string]$Dir
)

    if( !(Test-Path $Dir) ){
        Write-warning "Supplied directory was not found!"
        return
    }
    $PATH = [Environment]::GetEnvironmentVariable("PATH", "Machine")
    if( $PATH -notlike "*"+$Dir+"*" ){
        [Environment]::SetEnvironmentVariable("PATH", "$PATH;$Dir", "Machine")
    }
}

You could make things better by doing some polishing. For example, using Test-Path to confirm that your directory actually exists.


for calling SetEnvironmentVariable with the Machine parameter you need to open the PowerShell with administrator rights
it's bitterly disappointing that this "power" shell doesn't recognize %userprofile% nor $userprofile.. but then again, this is windows we're talking about
@abbood What you're looking for is $env:userprofile.
You should also specify either user or machine in the call of GetEnvironmentVariable. Otherwise, $PATH will contain the value of both the user and machine part of the registry which will unecessarily blow up the path variable when storing it again.
D
Dave Jarvis

Safer SETX

Nod to all the comments on the @Nafscript's initial SETX answer.

SETX by default will update your user path.

SETX ... /M will update your system path.

%PATH% contains the system path with the user path appended

Warnings

Backup your PATH - SETX will truncate your junk longer than 1024 characters Don't call SETX %PATH%;xxx - adds the system path into the user path Don't call SETX %PATH%;xxx /M - adds the user path into the system path Excessive batch file use can cause blindness1

The ss64 SETX page has some very good examples. Importantly it points to where the registry keys are for SETX vs SETX /M

User Variables: HKCU\Environment System Variables: HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment

Usage instructions

Append to User PATH

append_user_path.cmd

@ECHO OFF
REM usage: append_user_path "path"
SET Key="HKCU\Environment"
FOR /F "usebackq tokens=2*" %%A IN (`REG QUERY %Key% /v PATH`) DO Set CurrPath=%%B
ECHO %CurrPath% > user_path_bak.txt
SETX PATH "%CurrPath%";%1

Append to System PATH

append_system_path.cmd. Must be run as administrator.

(It's basically the same except with a different Key and the SETX /M modifier.)

@ECHO OFF
REM usage: append_system_path "path"
SET Key="HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment"
FOR /F "usebackq tokens=2*" %%A IN (`REG QUERY %Key% /v PATH`) DO Set CurrPath=%%B
ECHO %CurrPath% > system_path_bak.txt
SETX PATH "%CurrPath%";%1 /M

Alternatives

Finally there's potentially an improved version called SETENV recommended by the ss64 SETX page that splits out setting the user or system environment variables.

Example

Here's a full example that works on Windows 7 to set the PATH environment variable system wide. The example detects if the software has already been added to the PATH before attempting to change the value. There are a number of minor technical differences from the examples given above:

@echo off
set OWNPATH=%~dp0
set PLATFORM=mswin

if defined ProgramFiles(x86)                        set PLATFORM=win64
if "%PROCESSOR_ARCHITECTURE%"=="AMD64"              set PLATFORM=win64
if exist "%OWNPATH%tex\texmf-mswin\bin\context.exe" set PLATFORM=mswin
if exist "%OWNPATH%tex\texmf-win64\bin\context.exe" set PLATFORM=win64

rem Check if the PATH was updated previously
echo %PATH% | findstr "texmf-%PLATFORM%" > nul

rem Only update the PATH if not previously updated
if ERRORLEVEL 1 (
  set Key="HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment"
  for /F "USEBACKQ tokens=2*" %%A in (`reg query %%Key%% /v PATH`) do (
    if not "%%~B" == "" (
      rem Preserve the existing PATH
      echo %%B > currpath.txt

      rem Update the current session
      set PATH=%PATH%;%OWNPATH%tex\texmf-%PLATFORM%\bin
      
      rem Persist the PATH environment variable
      setx PATH "%%B;%OWNPATH%tex\texmf-%PLATFORM%\bin" /M
    )
  )
)

1. Not strictly true


P
Peter Mortensen

Handy if you are already in the directory you want to add to PATH:

set PATH=%PATH%;%CD%

It works with the standard Windows cmd, but not in PowerShell.

For PowerShell, the %CD% equivalent is [System.Environment]::CurrentDirectory.


My Powershell says %CD% is not recognized.
@PauloMatos Could try using [System.Environment]::CurrentDirectory
P
Peter Mortensen

Aside from all the answers, if you want a nice GUI tool to edit your Windows environment variables you can use Rapid Environment Editor.

Try it! It's safe to use and is awesome!


Windows 10 has significantly improved the Path Environment variable editor now. Only took them 20 years to get round to it.
P
Peter Mortensen

Command line changes will not be permanent and will be lost when the console closes.

The path works like first comes first served.

You may want to override other already included executables. For instance, if you already have another version on your path and you want to add different version without making a permanent change on path, you should put the directory at the beginning of the command.

To override already included executables;

set PATH=C:\xampp\php;%PATH%;


P
Peter Mortensen

Use pathed from gtools.

It does things in an intuitive way. For example:

pathed /REMOVE "c:\my\folder"
pathed /APPEND "c:\my\folder"

It shows results without the need to spawn a new cmd!


gtools can be easily installed using e.g. scoop with a oneliner: scoop install gtools in case this is useful for anyone else
G
Grzegorz Gajos

Regarding point 2 I'm using a simple batch file that is populating PATH or other environment variables for me. Therefore, there is no pollution of environment variables by default. This batch file is accessible from everywhere so I can type:

c:\>mybatchfile
-- here all env. are available
c:\>php file.php

This is an important difference between *nix-es and Windows. The batch runs in the same shell, and changes to the environment stay after it exits (at session scope). However, this cuts both ways: a batch file can obliterate your environment. (BTW, on *nix-es you'd just have to source such a file, like . mybatchfile).
Hi @grzegorz-gajos, I was looking for exactly that, your link for more details gives 404. Any alternatives?
Sorry, the content from the link is no longer available. I removed.
P
Peter Mortensen

Checking the above suggestions on Windows 10 LTSB, and with a glimpse on the "help" outlines (that can be viewed when typing 'command /?' on the cmd), brought me to the conclusion that the PATH command changes the system environment variable Path values only for the current session, but after reboot all the values reset to their default- just as they were prior to using the PATH command.

On the other hand using the SETX command with administrative privileges is way more powerful. It changes those values for good (or at least until the next time this command is used or until next time those values are manually GUI manipulated... ).

The best SETX syntax usage that worked for me:

SETX PATH "%PATH%;C:\path\to\where\the\command\resides"

where any equal sign '=' should be avoided, and don't you worry about spaces! There isn't any need to insert any more quotation marks for a path that contains spaces inside it - the split sign ';' does the job.

The PATH keyword that follows the SETX defines which set of values should be changed among the System Environment Variables possible values, and the %PATH% (the word PATH surrounded by the percent sign) inside the quotation marks, tells the OS to leave the existing PATH values as they are and add the following path (the one that follows the split sign ';') to the existing values.


This did nothing when I tried it. Are you missing an equal sign?
S
Surendra Parchuru

Below solution worked perfectly

try below command in your windows terminal.

C:>setx PATH "C:\myfolder;%PATH%"

SUCCESS: Specified value was saved.

you can refer more on Here


P
Pranav Sharma

If you run the command cmd, it will update all system variables for that command window.


In a sense. What happens is that you start a new session within the current session. Leaving will require you call exit twice, first to close the new and then to close the first session (with the old environment).
P
Peter Mortensen

In a command prompt you tell Cmd to use Windows Explorer's command line by prefacing it with start.

So start Yourbatchname.

Note you have to register as if its name is batchfile.exe.

Programs and documents can be added to the registry so typing their name without their path in the Start - Run dialog box or shortcut enables Windows to find them.

This is a generic reg file. Copy the lines below to a new Text Document and save it as anyname.reg. Edit it with your programs or documents.

In paths, use \\ to separate folder names in key paths as regedit uses a single \ to separate its key names. All reg files start with REGEDIT4. A semicolon turns a line into a comment. The @ symbol means to assign the value to the key rather than a named value.

The file doesn't have to exist. This can be used to set Word.exe to open Winword.exe.

Typing start batchfile will start iexplore.exe.

REGEDIT4
;The bolded name below is the name of the document or program, <filename>.<file extension>

[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths\Batchfile.exe]

; The @ means the path to the file is assigned to the default value for the key.
; The whole path in enclosed in a quotation mark ".

@="\"C:\\Program Files\\Internet Explorer\\iexplore.exe\""

; Optional Parameters. The semicolon means don't process the line. Remove it if you want to put it in the registry

; Informs the shell that the program accepts URLs.

;"useURL"="1"

; Sets the path that a program will use as its' default directory. This is commented out.

;"Path"="C:\\Program Files\\Microsoft Office\\Office\\"

You've already been told about path in another answer. Also see doskey /? for cmd macros (they only work when typing).

You can run startup commands for CMD. From Windows Resource Kit Technical Reference

AutoRun

HKCU\Software\Microsoft\Command Processor

Data type Range Default value
REG_SZ  list of commands  There is no default value for this entry.

Description

Contains commands which are executed each time you start Cmd.exe.


P
Peter Mortensen

A better alternative to Control Panel is to use this freeware program from SourceForge called Pathenator.

However, it only works for a system that has .NET 4.0 or greater such as Windows 7, Windows 8, or Windows 10.


O
Oliver Baumann

I have installed PHP that time. Extracted php-7***.zip into C:\php\ Backup my current PATH environment variable: run cmd, and execute command: path >C:\path-backup.txt Get my current path value into C:\path.txt file (same way) Modify path.txt (sure, my path length is more than 1024 chars, windows is running few years) I have removed duplicates paths in there, like 'C:\Windows; or C:\Windows\System32; or C:\Windows\System32\Wbem; - I've got twice. Remove uninstalled programs paths as well. Example: C:\Program Files\NonExistSoftware; This way, my path string length < 1024 :))) at the end of path string add ;C:\php\ Copy path value only into buffer with framed double quotes! Example: "C:\Windows;****;C:\php\" No PATH= should be there!!! Open Windows PowerShell as Administrator. Run command:

setx path "Here you should insert string from buffer (new path value)"

Re-run your terminal (I use "Far manager") and check: php -v


P
Peter Mortensen

As trivial as it may be, I had to restart Windows when faced with this problem.

I am running Windows 7 x64. I did a manual update to the system PATH variable. This worked okay if I ran cmd.exe from the stat menu. But if I type "cmd" in the Windows Explorer address bar, it seems to load the PATH from elsewhere, which doesn't have my manual changes.

(To avoid doubt - yes, I did close and rerun cmd a couple of times before I restarted and it didn't help.)


Is there an explanation?
I don't know the technicality behind this, but Windows is just notorious with this, always restart first and only after that continue troubleshooting...
J
Janin

On Windows 10, I was able to search for set path environment variable and got these instructions:

From the desktop, right-click the very bottom-left corner of the screen to get the Power User Task Menu. From the Power User Task Menu, click System. In the Settings window, scroll down to the Related settings section and click the System info link. In the System window, click the Advanced system settings link in the left navigation panel. In the System Properties window, click the Advanced tab, then click the Environment Variables button near the bottom of that tab. In the Environment Variables window (pictured below), highlight the Path variable in the System variables section and click the Edit button. Add or modify the path lines with the paths you want the computer to access. Each different directory is separated with a semicolon, as shown below:

C:\Program Files;C:\Winnt;C:\Winnt\System32

The first time I searched for it, it immediately popped up the System Properties Window. After that, I found the above instructions.


k
kiriloff

Use these commands in the bash shell on Windows to append new location to the PATH variable

PATH=$PATH:/path/to/mydir

or prepend this location

PATH=/path/to/mydir:$PATH

In your case for instance do

PATH=$PATH:C:\xampp\php

You can echo $PATH to see the PATH variable in shell


c
cachius

How to open Environment Variables window from cmd.exe/Run... dialog

SystemPropertiesAdvanced and click "Environment Variables", no UAC

rundll32 sysdm.cpl,EditEnvironmentVariables direct, might trigger UAC

Via Can the environment variables tool in windows be launched directly? on serverfault.com.

How to open Environment Variables window from Explorer

Right click on "This PC" Click on "Properties" On the left panel of the window that pops up, click on "Advanced System Settings" Click on the "Advanced" tab Click on "Environment Variables" button at the bottom of the window

You can also search for Variables in the StartMenu Search.

Reference images how the Environment Variables window looks like:

Windows 10

https://i.stack.imgur.com/7IWua.png

Windows 7

https://i.stack.imgur.com/hLV0J.png

Windows XP

https://i.stack.imgur.com/hFL7N.png