Solutions 

1. check your max_connection in console or mysql console as below.

   1. ### In Console
      c:\mysql> mysqladmin -u root -p variables | grep max_connection
      | max_connections | 100  // ▶ This is console output
      
      or 
      
      ### In mysql-workbench
      mysql > show variables like '%max_connection%';
      +-----------------------------------------------+
      variable_name |      Value |
      +-----------------------------------------------+
      max_connections | 100
      +-----------------------------------------------+
      1 row in set ( 0.00sec)

      
      

2.  If you need to support more connections, you should set a larger value for this variable.
   

   1. ### in mysql config file  [ linux : my.cnf  / windows : my.ini]
      [mysqld]
      max_connections = 500
      
      or 
      
      ### in mysql
      mysql> set global max_connections=500;