AH00526: Syntax error on line 20 of /private/etc/apache2/extra/httpd-mpm.conf:
Invalid command 'LockFile', perhaps misspelled or defined by a module not included in the server configuration
解决方法：
第一步进入以下目录找到httpd-mpm.conf这个文件
/private/etc/apache2/extra/httpd-mpm.conf
第二步在文件中找到LockFile "/private/var/log/apache2/accept.lock"，用#注释掉如下
＃LockFile "/private/var/log/apache2/accept.lock"
第三步重新启动apache服务器
sudo apachectl -k restart