can not connect Mysql serve on localhost

There could be a few reasons why you're unable to connect to the MySQL server on localhost. Here are a few things you can try:

1. Make sure that the MySQL server is actually running on your localhost. You can check this by opening up the Command Prompt (Windows) or Terminal (Mac) and typing in "mysql -u root -p". If the server is running, you should be prompted to enter your MySQL root password.

2. Make sure that your MySQL username and password are correct. Sometimes people forget their login credentials, or they may have been changed without their knowledge. Double-check to make sure you're using the correct login information.

3. Make sure that your MySQL server is configured to allow remote connections. By default, MySQL is only set up to allow connections from the local machine. If you're trying to connect from a remote machine, you'll need to modify the MySQL configuration file to allow remote connections.

4. Check your firewall settings. If you have a firewall enabled on your computer or network, it may be blocking the MySQL port (usually 3306). Make sure that the port is open and that traffic is allowed through.

Hopefully, one of these solutions will help you connect to the MySQL server on localhost.