MySQL: plugin 'federated 'is disabled. Or 1067 error startup error and "service MySQL unexpectedly stopped" SOLUTION

MySQL startup reports a 1067 error. In the system log "service MySQL unexpectedly stopped", the MySQL Log is: "plugin 'federated 'is disabled"

I found a solution on the Internet:
1. Add a line to [mysqld] In my. ini file
Tmpdir = "D:/MySQL/data /"
After the modification, it still cannot be started or can be started, but the same problem occurs again after the shutdown. Then, I made the second step and restarted normally.

2. Delete all files in the data directory except the database folder, restart MySQL, and solve the problem.