localhost E-Mail-Versand funktioniert nicht

A parse error has occurred while processing the following JSON data:
2019-08-29 12:10:04 SMTP ERROR: Failed to connect to server: Ein Verbindungsversuch ist fehlgeschlagen, da die Gegenstelle nach einer bestimmten Zeitspanne nicht richtig reagiert hat, oder die hergestellte Verbindung war fehlerhaft, da der verbundene Host nicht reagiert hat. (10060)<br>
SMTP connect failed https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting<br>
{"success":true,"message":null,"messages":{"message":["Joomla\\CMS\\Mail\\Mail::__set_state(array(\n   'CharSet' => 'utf-8',\n   'Version' => '5.2.27',\n   'Priority' => NULL,\n   'ContentType' => 'text\/plain',\n   'Encoding' => '8bit',\n   'ErrorInfo' => '',\n   'From' => 'postmaster@localhost.com',\n   'FromName' => 'Postmaster',\n   'Sender' => '',\n   'ReturnPath' => '',\n   'Subject' => '',\n   'Body' => '',\n   'AltBody' => '',\n   'Ical' => '',\n   'MIMEBody' => '',\n   'MIMEHeader' => '',\n   'mailHeader' => '',\n   'WordWrap' => 0,\n   'Mailer' => 'smtp',\n   'Sendmail' => '\/usr\/sbin\/sendmail',\n   'UseSendmailOptions' => true,\n   'PluginDir' => '',\n   'ConfirmReadingTo' => '',\n   'Hostname' => '',\n   'MessageID' => '',\n   'MessageDate' => '',\n   'Host' => 'localhost.com',\n   'Port' => '25',\n   'Helo' => '',\n   'SMTPSecure' => '',\n   'SMTPAutoTLS' => true,\n   'SMTPAuth' => 1,\n   'SMTPOptions' => \n  array (\n  ),\n   'Username' => 'postmaster',\n   'Password' => 'postmaster',\n   'AuthType' => '',\n   'Realm' => '',\n   'Workstation' => '',\n   'Timeout' => 300,\n   'SMTPDebug' => 2,\n   'Debugoutput' => 'html',\n   'SMTPKeepAlive' => false,\n   'SingleTo' => false,\n   'SingleToArray' => \n  array (\n  ),\n   'do_verp' => false,\n   'AllowEmpty' => false,\n   'LE' => '\n',\n   'DKIM_selector' => '',\n   'DKIM_identity' => '',\n   'DKIM_passphrase' => '',\n   'DKIM_domain' => '',\n   'DKIM_private' => '',\n   'DKIM_private_string' => '',\n   'action_function' => '',\n   'XMailer' => ' ',\n   'smtp' => NULL,\n   'to' => \n  array (\n  ),\n   'cc' => \n  array (\n  ),\n   'bcc' => \n  array (\n  ),\n   'ReplyTo' => \n  array (\n  ),\n   'all_recipients' => \n  array (\n  ),\n   'RecipientsQueue' => \n  array (\n  ),\n   'ReplyToQueue' => \n  array (\n  ),\n   'attachment' => \n  array (\n  ),\n   'CustomHeader' => \n  array (\n  ),\n   'lastMessageID' => '',\n   'message_type' => '',\n   'boundary' => \n  array (\n  ),\n   'language' => \n  array (\n    'authenticate' => 'SMTP Error! Could not authenticate.',\n    'connect_host' => 'SMTP Error! Could not connect to SMTP host.',\n    'data_not_accepted' => 'SMTP Error! Data not accepted.',\n    'empty_message' => 'Empty message body',\n    'encoding' => 'Unknown encoding: ',\n    'execute' => 'Could not execute: ',\n    'file_access' => 'Could not access file: ',\n    'file_open' => 'File Error: Could not open file: ',\n    'from_failed' => 'The following from address failed: ',\n    'instantiate' => 'Could not start mail function.',\n    'invalid_address' => 'Invalid address',\n    'mailer_not_supported' => 'Mailer is not supported.',\n    'provide_address' => 'You must provide at least one recipient email address.',\n    'recipients_failed' => 'SMTP Error! The following recipients failed: ',\n    'signing' => 'Signing error: ',\n    'smtp_connect_failed' => 'SMTP connect failed',\n    'smtp_error' => 'SMTP server error: ',\n    'variable_set' => 'Can\\'t set or reset variable: ',\n    'extension_missing' => 'Extension missing: ',\n  ),\n   'error_count' => 0,\n   'sign_cert_file' => '',\n   'sign_key_file' => '',\n   'sign_extracerts_file' => '',\n   'sign_key_pass' => '',\n   'exceptions' => true,\n   'uniqueid' => '',\n))"],"notice":["SMTP connect failed https:\/\/github.com\/PHPMailer\/PHPMailer\/wiki\/Troubleshooting"],"error":["Test mail could not be sent."]},"data":false}