Step by Step Install Open Source Pymol 2.x in Windows by Conda

This post was first released at 2019-05-26, and updated at 2021-04-20.

Since PyMOL 2.x released, there were no binary installer avaliable for Windows.

PyMOL Wiki provides the way to install open source PyMOL in Windows under Python 3.x.

PyMOL logo

This post provided the method to install PyMOL 2.x by conda (Anaconda or Minoconda) in Windows.

1. Install Conda

Download Anaconda or Miniconda and install it.

Since I am using Windows 10 64 bit version, miniconda3-py3.8 was installed.

E.g., Miniconda3 was installed at D:\miniconda3.

2. Create PyMOL envrionment

Click Start menu, and run “Anaconda Prompt (miniconda3)”.

Input next command to create a virtual environment pymol:

conda create -n pymol

Then, activate created environment

conda activate pymol

3. Install supporting packages

conda install -c conda-forge pip numpy pmw

All other supporting packages would be installed automatically.

4. Download PyMOL whl files

Download pre-compiled Open-Source PyMOL from Christoph Gohlke of the Laboratory for Fluorescence Dynamics, University of California, Irvine:

Here listed lots of pre-compiled distributions. The filename format is:

           \        \          \
            \        \          \__ for 64 bit Windows
             \        \
              \        \___________ for Python 3.8.x 
                \__________________ PyMOL version 2.4.0

Download both “pymol.whl” and “pymol_launcher.whl” files.

Here pymol-2.4.0-cp38-cp38-win_amd64.whl and pymol_launcher-2.1-cp38-cp38-win_amd64.whl were downloaded.

5. Install whl files

  • In the conda pymol environment, switch to download directory (e.g., D:\Downloads)
# Switch to Drive D:
# Enter the directory
cd Downloads
  • Install pymol_launcher first
pip install --no-index --find-links="%CD%" pymol_launcher-2.1-cp38-cp38-win_amd64.whl

Output would be like:

Looking in links: D:\Downloads
Processing D:\downloads\pymol_launcher-2.1-cp38-cp38-win_amd64.whl
Processing D:\downloads\pymol-2.4.0-cp38-cp38-win_amd64.whl
Requirement already satisfied: numpy in D:\miniconda3\envs\pymol\lib\site-packages (from pymol->pymol-launcher==2.1) (1.20.2)
Requirement already satisfied: Pmw in D:\miniconda3\envs\pymol\lib\site-packages (from pymol->pymol-launcher==2.1) (2.0.1)
Installing collected packages: pymol, pymol-launcher
Successfully installed pymol-2.4.0 pymol-launcher-2.1

You might have noticed PyMOL has been installed automatically.

To update PyMOL later, run

pip install --upgrade --no-deps pymol-2.4.0-cp38-cp38-win_amd64.whl

The pymol_launcher do not need update.

6. Launch pymol

In an activated pymol environment, run


Then, the PyMOL will be launched. Have fun!

7. New single windows interface

Note: If you’d like to install PyMOL extend scripts, you do not need to install PyQt5 separately.

Follow instructions in Section 8.

If you’d like to use the newer single-window Qt interface, simply install the PyQt5, also under the pymol environment:

pip install pyqt5

The new interface would be like:

PyMol single-window interface

8. Install PyMOL extend scripts

(1) Install necessary packages:

conda install -c conda-forge scipy matplotlib wxpython

(2) Download script/plugin collection:

git clone

(3) Next copy the directory “Pymol-script-repo/” to PYMOL_PATH:


PYMOL_PATH can be determined by running the following command from within PyMOL:

print os.environ['PYMOL_PATH']

(4) Then create a file “” under the directory D:\miniconda3\envs\pymol\Lib\site-packages\pymol\pymol_path, it content is:

# Add paths to sys.path so PyMOL can find modules and scripts
import sys, os
pymol_git = os.path.abspath(os.path.join(os.environ['PYMOL_PATH'], 'Pymol-script-repo'))
os.environ['PYMOL_GIT_MOD'] = os.path.join(pymol_git,'modules')

# Make setting changes to Plugin Manager
import pymol.plugins
pymol.plugins.preferences = {'instantsave': False, 'verbose': False}
pymol.plugins.autoload = {'apbs_tools': False}
pymol.plugins.set_startup_path([os.path.join(pymol_git, 'plugins'), os.path.join(sys.prefix, 'Lib', 'site-packages', 'pmg_tk', 'startup')])
pymol.plugins.preferences = {'instantsave': True, 'verbose': False}

(5) Lanuch PyMOL, you’ll find extend scripts under the Menu Plugins->Legacy Plugins:

Install PyMOL Plugins

Note: There are still some un-solved errors:

module 'base64' has no attribute 'encodestring'
Unable to initialize plugin 'bnitools' (pmg_tk.startup.bnitools).
No module named 'tkintertable'
Unable to initialize plugin 'mtsslDockGui' (pmg_tk.startup.mtsslDockGui).
use() got an unexpected keyword argument 'warn'
Unable to initialize plugin 'mtsslPlotter' (pmg_tk.startup.mtsslPlotter).
D:\miniconda3\envs\pymol\lib\site-packages\wx\lib\pubsub\ wxPyDeprecationWarning: wx.lib.pubsub has been deprecated, plese migrate your code to use pypubsub, available on PyPI.
  warnings.warn('wx.lib.pubsub has been deprecated, plese migrate your '

Optimize plug-in needs openbabel to be installed in your system, please follow the instructions at

No module named 'cctbx'
Unable to initialize plugin 'SuperSymPlugin' (pmg_tk.startup.SuperSymPlugin).
 Detected OpenGL version 1.1. Shaders and volumes unavailable.
 OpenGL graphics engine:
  GL_VENDOR:   Microsoft Corporation
  GL_VERSION:  1.1.0


  1. PyMOL Wiki: Windows Install