Plesk is not accessible and PleskSQL server can not be started: The system cannot find the file specified. (Error code 2)

Symptoms

• Plesk is not accessible with one of the following errors:

  HTTP Error 503. The service is unavailable.

  or

  Server Error
  500 Plesk\Exception\Database
  DB query failed: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it.
  Type Plesk\Exception\Database
  Message DB query failed: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it.
  File Mysql.php
  Line 79

• Unable to generate a one-time login link, the following error is provided:

  plesk login
  DB query failed: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it.

• PleskSQLServer service can not be started with:

  The system cannot find the file specified. (Error code 2) at StartService 'PleskSQLServer'
  at (service::startService line 211)
  at Unablr to call startService(PleskSQLServer)(service::startService line 274)

Cause

The Path to executable in Services > Plesk SQL Server > Properties is pointing to the non-existent file:

"C:\Program Files (x86)\Plesk"MySQL\bin\mysqld.exe" --defaults-file="C:\Program Files (x86)\Plesk\MySQL\my.ini" PleskSQLServer

The file C:\Program Files (x86)\Plesk\"MySQL\bin\mysqld.exe is absent on the server.

Resolution

1. Connect to the server via RDP.
2. Copy the mysqld.exe file from a clean environment to the C:\Program Files (x86)\Plesk\"MySQL\bin\ directory.