sudo apachectl -f /usr/local/apache2/conf/httpd.conf -k start

httpd: Syntax error on line 62 of /usr/local/apache2/conf/httpd.conf:
Cannot load modules/mod_authn_file.so into server:
dlopen(/Applications/MAMP/Library/modules/mod_authn_file.so, 10):
Symbol not found: _ap_log_rerror
Referenced from: /Applications/MAMP/Library/modules/mod_authn_file.so
Expected in: flat namespace
in /Applications/MAMP/Library/modules/mod_authn_file.so