How do I add to the Windows PATH variable using se

Question

I want to modify the Windows PATH variable using setx. The following works at least 50% of the time on Windows 8:

setx PATH %PATH%;C:\Python27\;C:\Python27\Scripts\

If it gives the error "the default argument can only be used 2 times", then the following works some of the time:

setx PATH "%PATH%;C:\Python27\;C:\Python27\Scripts\"

The difference is that we wrapped the second argument in quotes. I believe the quotes are necessary when %PATH% expands to include spaces.

However, I have encountered some weird problems on Windows 7. On one particular Windows 7 machine, I had this problem:

echo %PATH%

It prints:

C:\Foo\;C:\Bar\;[...lots of stuff...]C:\Baz\

Then I do this:

setx PATH "%PATH%;C:\Quux\"

Then it says "Error: Truncated at 1,024 characters." Now let's check what PATH contains:

echo %PATH%

It prints:

C:\Foo\;C:\Foo\;C:\Bar\;C:\Bar\;[...lots of stuff, now duplicated...]C:\B

...and it is cut off at 1,024 characters. It ran over because of the duplicates. Also interesting: The value of PATH changes despite the fact that setx raised an error and did not say "Success".

I was able to repeat this strange behavior several times (luckily I had saved the original contents of PATH).

At the moment, the only surefire way I know to append to the PATH is the following:

1. echo the PATH.

2. Copy the contents of PATH into a text file and manually add ;C:\Python27\;C:\Python27\Scripts\ to the end of the PATH.

3. Copy the whole thing out of the text file.

4. setx PATH "<paste the string here>"

That process works every single time on both Windows 7 and Windows 8.

I should really be able to do this in one command. What am I doing wrong?

Thank you.

Answer 1

This works perfectly:

for /f "usebackq tokens=2,*" %A in (`reg query HKCU\Environment /v PATH`) do set my_user_path=%B

setx PATH "C:\Python27;C:\Python27\Scripts;%my_user_path%"

The 1st command gets the USER environment variable 'PATH', into 'my_user_path' variable The 2nd line prepends the 'C:\Python27;C:\Python27\Scripts;' to the USER environment variable 'PATH'

Answer 2

I was facing the same problems and found a easy solution now.

Using pathman.

pathman /as %M2%

Adds for example %M2% to the system path. Nothing more and nothing less. No more problems getting a mixture of user PATH and system PATH. No more hardly trying to get the correct values from registry...

Tried at Windows 10

Answer 3

Steps: 1. Open a command prompt with administrator's rights.

Steps: 2. Run the command: setx /M PATH "path\to;%PATH%"

[Note: Be sure to alter the command so that path\to reflects the folder path from your root.]

Example : setx /M PATH "C:\Program Files;%PATH%"

Answer 4

Without admin rights the only way that worked for me is a bat file that contains the following code:

for /F "tokens=2* delims= " %%f IN ('reg query HKCU\Environment /v PATH ^| findstr /i path') do set OLD_SYSTEM_PATH=%%g
setx PATH "%USERPROFILE%\wev-tools;%OLD_SYSTEM_PATH%"

The code is the combination of the answers https://stackoverflow.com/a/45566845/4717152 and https://stackoverflow.com/a/10292113/4717152

Answer 5

If someone want to run it in PowerShell it works like below,

Run Powershell as Administrator

Then

setx /M PATH "$Env:PATH;<path to add>"

To verify, open another Powershell and view PATH as below,

$Env:PATH

Answer 6

I was having such trouble managing my computer labs when the %PATH% environment variable approached 1024 characters that I wrote a Powershell script to fix it.

You can download the code here: https://gallery.technet.microsoft.com/scriptcenter/Edit-and-shorten-PATH-37ef3189

You can also use it as a simple way to safely add, remove and parse PATH entries. Enjoy.