This is usually a PostgreSQL installation issue, not an Odoo issue. Since the PostgreSQL cluster failed to initialize, Odoo cannot connect to the database, which explains the "Access Denied" message.

I'd recommend the following steps:

1. Completely uninstall PostgreSQL (and pgAdmin if installed), then delete the PostgreSQL data directory (e.g., C:\Program Files\PostgreSQL\ and C:\ProgramData\PostgreSQL\) before reinstalling.
2. Run the installer as Administrator.
3. Temporarily disable ESET (or any antivirus) or add PostgreSQL/Odoo installer exclusions, as security software can sometimes block PostgreSQL's post-install scripts.
4. Check the PostgreSQL installation logs (usually under %TEMP% or the PostgreSQL installer log) for the exact reason the cluster initialization failed.
5. Verify that port 5432 is not already in use and that no previous PostgreSQL service is still running.
6. After PostgreSQL installs successfully, confirm the postgresql-x64-xx service is running in Services before starting Odoo.

If the PostgreSQL installation succeeds, Odoo should be able to connect normally.

If you're still having trouble, please share:

• The PostgreSQL version being installed.
• Whether you're using the official Odoo installer or installing PostgreSQL separately.
• The contents of the PostgreSQL installation log (especially around the "database cluster initialization failed" message).