Today I had to install mailparse via PEAR. On installing I came across one of the errors: mbstring not found despite of it was right there. One of the simplest option to fix it is given below. Though I am working on MAMP but it will work with anyone since it’s part of PHP Source. Go to your PHP Source Library. In my case it is: /Applications/MAMP/bin/php/php7.0.8/include/php/ext/mbstring/libmbfl/mbfl and add following lines in mbfilter.h #undef HAVE_MBSTRING #define HAVE_MBSTRING 1 and then run PEAR command again pear install pecl/mailparse If all goes well it should give something like: Build process completed successfully Installing '/Applications/MAMP/bin/php/php7.0.8/lib/php/extensions/no-debug-non-zts-20151012/mailparse.so' install ok: channel://pecl.php.net/mailparse-3.0.1 configuration option "php_ini" is not set to…