Unable to use Python in ArcGIS Pro when using a cloned environment

Description

When attempting to use Python in ArcGIS Pro using a cloned environment, the initialization process fails and returns the following error messages in the Python window and Python notebook:

The Python window

Error:
Failed to Initialize Python Interpreter

The Python notebook

Error:
Failed to create notebook server

In addition, running the Python Command Prompt returns the following error message:

Error:
CMD does not support UNC paths as current directories.

Cause

This issue occurs when the cloned Python environment is located on a network location with Universal Naming Convention (UNC) paths. By design, Python Package Manager is unable to read Python environments with UNC paths. The image below shows an example of a cloned Python environment located on a network location with UNC paths in the Environment Manager dialog box.

Solution or Workaround

To solve this issue, follow the steps provided below to create a symbolic link to the directory of the cloned Python environment with a Universal Naming Convention (UNC) path and add the symbolic link in ArcGIS Pro.

1. In the Windows search box on the taskbar, search for and right-click Windows Command Prompt, then select Run as administrator.

2. In the Administrator: Command Prompt window, run the following command to create a symbolic link between the local folder and the cloned Python environment file path.

mklink /D <local_folder_location>\<file_name> <network_folder_location>

Note: 
Enclose the folder name in double quotes (" ") if the folder name contains spaces. For example, "C/DESKTOP/ENV TEST 1".

3. Navigate to the symbolic link created in Step 2 and copy the file path.

4. Open the project in ArcGIS Pro. At the top ribbon, click the Project tab.

5. In the list of side tabs, click Package Manager.

6. In the Package Manager window, click the Environment Manager button.

7. In the Environment Manager dialog box, click the Add existing environment button.

8. In the Browse Environments dialog box, paste the file path copied in Step 3 in the Name box and click OK.

9. In the Environment Manager dialog box, hover over and double-click the newly added Python environment to activate the environment. Click OK.