Try
Start.Query.SQL.Clear;
Start.Query.SQL.Add('INSERT INTO `Users` VALUES (null, ''LUserName'', ''LPassWord'', ''LPassWordRecovery'',''LLastName'', ''LName'', ''LMiddleName'', ''sLProfession'', False)');
Start.Query.ExecSQL;
Except
Application.MessageBox('Внимание! Ошибка регистрации.', 'Error', MB_OK+MB_ICONERROR);
exit();
End;