在我的ubuntu 14.04, apache 2.4, php 5.5.9安装，我尝试在/var/www/html(默认文档根)上使用sample.php，它工作正常。 所以问题出在我的虚拟服务器配置上。 解决方案是在包含.php的Directory def中包含这一行:

    php_admin_flag engine on

我发现了另一个导致这个问题的问题，并且已经解决了它。我不小心将脚本保存为UTF-16编码。PHP5似乎不能识别<?PHP标签默认为16位编码。

听起来你的配置好像有问题，下面是一些你可以检查的东西:

Make sure that PHP is installed and running correctly. This may sound silly, but you never know. An easy way to check is to run php -v from a command line and see if returns version information or any errors. Make sure that the PHP module is listed and uncommented inside of your Apache's httpd.conf This should be something like LoadModule php5_module "c:/php/php5apache2_2.dll" in the file. Search for LoadModule php, and make sure that there is no comment (;) in front of it. Make sure that Apache's httpd.conf file has the PHP MIME type in it. This should be something like AddType application/x-httpd-php .php. This tells Apache to run .php files as PHP. Search for AddType, and then make sure there is an entry for PHP, and that it is uncommented. Make sure your file has the .php extension on it, or whichever extension specified in the MIME definition in point #3, otherwise it will not be executed as PHP. Make sure you are not using short tags in the PHP file (<?), these are not enabled on all servers by default and their use is discouraged. Use <?php instead (or enable short tags in your php.ini with short_open_tag=On if you have code that relies on them). Make sure you are accessing your file over your webserver using an URL like http://localhost/file.php not via local file access file://localhost/www/file.php

最后，查看PHP手册以获得更多的设置技巧。

如果你使用Apache 2.4，在httpd.conf文件中添加AddType application/x-httpd-php .php

我也遇到过类似的问题，但我的解决方法不同。 存放PHP代码的文件名为somename。html 把它改为" someename .php"工作得很好

在我的情况下，php模块没有加载。试试这个:

检查加载了哪些模块:apache2ctl -M。查找类似php7_module (shared)的模块 如果没有列出php模块，则尝试加载与您的php版本对应的模块。在我的例子中，php包是libapache2-mod-php7.3。所以我这样做了:a2enmod php7.3，问题就解决了。