Access denied for user 'root'@'localhost'

Q: Fix the password in application.properties

When to use: Use this if you recently changed your DB password or copied the project from another machine.. The 'using password: YES' part of the error means Spring sent a password, but it was incorrect. Update it to match the DB.

Q: Remove trailing spaces from the URL/credentials

When to use: Use this if you are 100% sure the password is correct but it still fails.. A hidden space at the end of the username or password in properties files is a very common cause of authentication failures.

Q: Grant privileges to the database user

When to use: Use this if the user exists but doesn't have permission to access the specific database.. Log into your database via command line and grant all privileges to the user for that specific schema.

🔴 The Error You're Seeing

Confirm this matches your console output. If it does, you're in the right place.

ERROR LOG

2026-02-14 17:25:12.000 ERROR 8842 --- [           main] com.zaxxer.hikari.pool.HikariPool        : HikariPool-1 - Exception during pool initialization.

java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
	at com.zaxxer.hikari.pool.HikariPool.newConnection(HikariPool.java:345)

⚡ Quick Fix Works 80% of the time

Verify the spring.datasource.username and spring.datasource.password in application.properties.

spring.datasource.username=root
spring.datasource.password=your_correct_password

🛠️ Solutions (3 Ways to Fix)

Solution 1✓ Most common cause

Fix the password in application.properties

👉 Use this if you recently changed your DB password or copied the project from another machine.

The 'using password: YES' part of the error means Spring sent a password, but it was incorrect. Update it to match the DB.

spring.datasource.username=root
spring.datasource.password=mySecretPassword123

Solution 2

Remove trailing spaces from the URL/credentials

👉 Use this if you are 100% sure the password is correct but it still fails.

A hidden space at the end of the username or password in properties files is a very common cause of authentication failures.

# Bad (trailing space after root)
# spring.datasource.username=root 

# Good
spring.datasource.username=root

Solution 3

Grant privileges to the database user

👉 Use this if the user exists but doesn't have permission to access the specific database.

Log into your database via command line and grant all privileges to the user for that specific schema.

-- Log into MySQL/Postgres as admin
GRANT ALL PRIVILEGES ON mydb.* TO 'root'@'localhost';
FLUSH PRIVILEGES;

📋 Version Notes

Spring Boot 2.x

Standard JDBC authentication error.

Spring Boot 3.x

Standard JDBC authentication error. MySQL connector uses com.mysql.cj.jdbc.exceptions.SQLError.

🧠 Why this Happens

Tap to expand the deep technical explanation

Spring Boot successfully connected to the database server (unlike Connection Refused), but the database server rejected the username and password combination you provided.

The HITEC City Parking Spot Analogy:

It is like using the wrong PIN at an ATM. The ATM (database server) is working, but it refuses to give you access to the money because your credentials are wrong.

🛡️ How to Prevent This Next Time

Store database credentials in environment variables (e.g., ${DB_PASSWORD}) rather than hardcoding them, to prevent typos during deployments.