If you get the following error message in PHP, it means the mailparse
PHP extension is missing.
Call to undefined function mailparse_msg_create()
1. Install mailparse via PECL
You can install the mailparse extension via PECL, using the following command:
pecl install mailparse
Note: if you get an error saying /bin/sh: re2c: command not found
then look over here for the solution on how to install it.
2. Add mailparse extension to PHP.ini
After installing the mailparse extension, activate it by appending the following to the end your PHP.ini file.
extension=mailparse.so
Afterwards, restart php-fpm or apache/httpd. For example for CentOS 8 you would use:
service httpd restart
Now the mailparse extension should be available to PHP and the error message should dissappear!