PgAdmin4 - 'NoneType' object has no attribute 'value'

[Derek van den Nieuwenhuijzen]

Hi Postgress,

I used to have a functioning PostgreSQL database, but upon reinstalling due to 
computer issues, I am now getting this error after launching:

Traceback (most recent call last):
  File "C:\Program Files\PostgreSQL\12\pgAdmin 4\web\pgAdmin4.py", line 98, in 
<module>
    app = create_app()
  File "C:\Program Files\PostgreSQL\12\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\12\pgAdmin 
4\web\pgadmin\setup\db_version.py", line 19, in get_version
    return version.value
AttributeError: 'NoneType' object has no attribute 'value'

I've tried everything from these stackoverflow forums 
(https://stackoverflow.com/questions/43211296/pgadmin4-postgresql-application-server-could-not-be-contacted
 and 
https://stackoverflow.com/questions/67559636/pgadmin4-nonetype-object-has-no-attribute-value/67570989#67570989)
 in order to fix it, however the error remains. I'm out of options, hopefully 
you know the answer.

I tried it with both PostgreSQL 11, 12 and 13. I'm using a windows 64 bit with 
PgAdmin 4.

Kind regards,

Derek
[https://cdn.sstatic.net/Sites/stackoverflow/Img/apple-touch-i...@2.png?v=73d79a89bded]<https://stackoverflow.com/questions/43211296/pgadmin4-postgresql-application-server-could-not-be-contacted>
configuration - pgadmin4 : postgresql application server could not be 
contacted. - Stack 
Overflow<https://stackoverflow.com/questions/43211296/pgadmin4-postgresql-application-server-could-not-be-contacted>
I have installed PostgreSQL 9.6.2 on my Windows 8.1. But the pgadmin4 is not 
able to contact the local server. I have tried several solutions suggested here 
in stackoverflow, tried to uninstall and reinstall PostgreSQL 9.6.2 , tried to 
modify the config.py, config_distro.py, and delete the files in Roaming 
folder,i tried standalone pgadmin4 installation, but no success.However, in my 
local ...
stackoverflow.com