1. Make sure PostgreSQL is installed on your laptop.
2. Start the PostgreSQL service (sudo service postgresql start on Linux, or use pgAdmin on Windows).
3. Check Odoo’s config has the correct db_user and db_password.
4. Verify PostgreSQL is listening on the expected port (usually 5432).
5. Restart Odoo after fixing the DB connection.

Hi,

Please refer to the following links: 

https://www.cybrosys.com/blog/how-to-install-odoo-18-on-ubuntu-24-04-lts-server

https://www.cybrosys.com/blog/how-to-setup-odoo-18-development-environment-using-pycharm-in-ubuntu-22-04

Hope it helps.

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