Just made a try with MailOptin, but just like @chinook65 I wasn’t able to activate the plugin.
So for now we are sende Mailchimp news letter by using the email beamer from Mailchimp.
The error text when activating MailOptin:
Parse error: syntax error, unexpected ‘[‘ in /home/www/ikast-am.dk/wp-content/plugins/mailoptin/vendor/guzzlehttp/psr7/src/functions.php on line 78
Fatal Error (hide details) (remove)
The site encountered a problem that it cannot recover from. Please use the following information to try to resolve the problem.
Error Message
Fatal Error: syntax error, unexpected ‘[‘ in /home/www/ikast-am.dk/wp-content/plugins/mailoptin/vendor/guzzlehttp/psr7/src/functions.php on line 78
Description
The MailOptin – Lite plugin code created an error that caused PHP execution to fail.
This type error is called a “syntax error.” A syntax error means that the format of the code is invalid. Examples of syntax errors: a missing semicolon after a line of code, having mismatched parentheses, forgetting to put a dollar sign ($) in front of a variable’s name, and forgetting an operator — such as a plus sign (+) — between two variables. There are many other possible causes of syntax errors, the preceding are just a few examples.
Solutions
Invalid code modifications can cause this problem. If you have made any modifications to the plugin, remove them and try to load the site again.
It is possible that this plugin’s code is out of date and that an upgrade is available. Check with the plugin’s author to see if an upgrade is available.
There may be a conflict with another plugin running on the site. Try upgrading the other plugins on the site. A plugin conflict can be ruled out by deactivating all the other active plugins on the site and checking to see if the error still occurs.
The MailOptin – Lite plugin may not have been fully uploaded. Uploading the plugin again could fix the issue. Important: If you do this, you will lose any modifications made to the plugin.
Error Source Details
Type Plugin
Name MailOptin – Lite
Version 1.2.7.0
Author MailOptin Team
Path /home/www/ikast-am.dk/wp-content/plugins/mailoptin
File vendor/guzzlehttp/psr7/src/functions.php
Other Software Details
WordPress Version 4.9.8
PHP Version 5.3.29
Full Error Details
Type Parse Error (E_PARSE)
Message syntax error, unexpected ‘[‘
File /home/www/ikast-am.dk/wp-content/plugins/mailoptin/vendor/guzzlehttp/psr7/src/functions.php
Line 78
Type Description This type of error indicates that the PHP code is invalid and is typically referred to as a syntax error. It basically means that the code was written incorrectly and is preventing PHP from being able to read the code properly.
Note that this message is generated by iThemes.com products when an error is encountered on the site. While an iThemes product is generating this message, it is not necessarily the cause of the problem.