fatal error: server could not be contacted when running pgAdmin4. ‘NoneType’ object has no attribute ‘value’

To solve fatal error: server could not be contacted when running pgAdmin4. ‘NoneType’ object has no attribute ‘value’ error follow below methods.

ERROR LOG

Traceback (most recent call last):
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgAdmin4.py", line 98, in <module>
    app = create_app()
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgadmin\__init__.py", line 347, in create_app
    if not os.path.exists(SQLITE_PATH) or get_version() == -1:
  File "C:\Program Files\PostgreSQL\13\pgAdmin 4\web\pgadmin\setup\db_version.py", line 19, in get_version
    return version.value
AttributeError: 'NoneType' object has no attribute 'value'

How to solve fatal error: server could not be contacted when running pgAdmin4. ‘NoneType’ object has no attribute ‘value’ ?

To fix the fatal error: server could not be contacted when running pgAdmin4. ‘NoneType’ object has no attribute ‘value’ issue. I found a temporary solution in which you may execute the “pgAdmin 4” software in Python.

1. First of all delete C:\Users\username\AppData\Roaming\pgadmin.
2. Open the terminal.
3. Run C:\Program Files\PostgreSQL\12\pgAdmin 4\web\pgAdmin4.py file using python
4. Run as administrator the “pgAdmin 4” app from the windows menu and it will work as expected.

Alternative to Solve fatal error: server could not be contacted when running pgAdmin4. ‘NoneType’ object has no attribute ‘value’

As it is the pgAdmin issue that is ‘NoneType’ object has no attribute ‘value’, the standalone pgAdmin can be installed without any errors from pgadmin.org/download. It appears this is a common bug that has been reported on the pgAdmin bug list, here and here

Hope the above solution works.

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