To modify the PostgreSQL password on Windows, you can follow these steps:

Step 1: Access PostgreSQL Command Line

1. Open the Command Prompt.

2. Navigate to the PostgreSQL installation directory. Typically, this is located at:

   C:\Program Files\PostgreSQL\<version>\bin
   

   Replace <version> with the version number of your PostgreSQL installation. You can change the directory using the following command:

   cd "C:\Program Files\PostgreSQL\<version>\bin"
   

Step 2: Connect to PostgreSQL

1. Connect to the PostgreSQL database using the following command:

   psql -U postgres
   

   You will be prompted to enter the current password for the postgres user.

Step 3: Change the Password

1. Once logged in, change the password using the following SQL command:

   ALTER USER postgres PASSWORD '<new_password>';
   

   Replace <new_password> with your desired new password. Ensure that the new password is strong and meets security guidelines.

Step 4: Exit PostgreSQL

1. After changing the password, exit the PostgreSQL command line by typing:

   \q
   

Step 5: Verify the Password Change

1. To verify that the password change was successful, try logging in with the new credentials:

   psql -U postgres -W
   

   Enter the new password when prompted.

Optional: Modify pg_hba.conf (if needed)

If you encounter issues with password authentication, you may need to modify the pg_hba.conf file: 1. Locate the pg_hba.conf file in your PostgreSQL data directory, typically found at:

   C:\Program Files\PostgreSQL\<version>\data

1. Open the file in a text editor and change the authentication method for local connections from peer or scram-sha-256 to md5 or trust:

   local all postgres md5
   

2. Save the file and restart the PostgreSQL service.

Troubleshooting Tips

• If you have forgotten the current password, you can reset it by temporarily changing the authentication method in pg_hba.conf to trust and following the steps above.
• Ensure that you edit the correct version of the pg_hba.conf file if you have multiple PostgreSQL installations.

By following these steps, you should be able to successfully modify the PostgreSQL password on Windows.