How to add to the PYTHONPATH in Windows, so it finds my modules/packages?

You know what has worked for me really well on windows.

My Computer > Properties > Advanced System Settings > Environment Variables >

Just add the path as C:\Python27 (or wherever you installed python)

OR

Then under system variables I create a new Variable called PythonPath. In this variable I have C:\Python27\Lib;C:\Python27\DLLs;C:\Python27\Lib\lib-tk;C:\other-folders-on-the-path

This is the best way that has worked for me which I hadn't found in any of the docs offered.

EDIT: For those who are not able to get it,Please add

C:\Python27;

along with it. Else it will never work.

Windows 7 ProfessionalI Modified @mongoose_za's answer to make it easier to change the python version:

1. [Right Click]Computer > Properties >Advanced System Settings > Environment Variables
2. Click [New] under "System Variable"
3. Variable Name: PY_HOME, Variable Value:C:\path\to\python\version
4. Click [OK]
5. Locate the "Path" System variable and click [Edit]

6. Add the following to the existing variable:

   %PY_HOME%;%PY_HOME%\Lib;%PY_HOME%\DLLs;%PY_HOME%\Lib\lib-tk;

7. Click [OK] to close all of the windows.

As a final sanity check open a command prompt and enter python. You should see

>python [whatever version you are using]

If you need to switch between versions, you only need to modify the PY_HOME variable to point to the proper directory. This is bit easier to manage if you need multiple python versions installed.

From Windows command line:

set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib

To set the PYTHONPATH permanently, add the line to your autoexec.bat. Alternatively, if you edit the system variable through the System Properties, it will also be changed permanently.