You might receive the error Column count of mysql.user is wrong. Expected 42, found 44. The table is probably corrupted , this is probably because you import the whole database from mysql 5.6 to 5.7 . The table structure has changed , so you need to update it. You can use the command mysql_upgrade to do this work for you.

After you import the data , run this file

mysql_upgrade -uroot -p -h127.0.0.1 -P3306


this command will go all over your databases table and upgrade the database structure .

mysql.tables_priv OK
mysql.time_zone OK
mysql.time_zone_leap_second OK
mysql.time_zone_name OK
mysql.time_zone_transition OK
mysql.time_zone_transition_type OK
mysql.user OK
Upgrading the sys schema.