In most cases for the error PHP version: Not installed, when you manually run php.exe it throws MSVCR110.dll is missing. You should install Visual C++ Redistributable for Visual Studio 2012 - with the same architecture as downloaded php interpreter.

So, you mean to highlight all pieces of code that will not work with the PHP version you are writing it in, right? That can be done here:

Preferences -> Languages & Frameworks > PHP

and the same on Mac:

PhpStorm -> Preferences (⌘,) -> Languages & Frameworks > PHP

Or with newer versions of PhpStorm in Windows:

File -> Settings -> Languages & Frameworks > PHP

then select your PHP version, for example, 7.0

This is very useful when your local system runs PHP 7.0, for example, but production is running PHP 5.5.

That way PhpStorm will warn you which parts will not work in production, show proper hints during writing code according to the selected version, etc.

If this happens and you see the red I with PHPUnit Version not installed then you probably get the message "Please select PHP Interpreter to load PHPUnit version" when you press the refresh button.

If you have the path to phpunit.phar set and your path the composer autoloader is fine, then it is possible that PHPStorm simply doesn't get what PHP exe file to use to load the PHPUnit.

You can then choose to add a Remote PHP Interpreter but you may also choose to add a local PHP Interpreter (for instance if you have XAMPP or WAMPP or LAMPP installed on your computer).

Press Ctrl+Alt+S and go to -> Languages & Frameworks -> PHP -> CLI Interpreter -> go for the button with the dots (or shift + enter) and there you can add an "Interpreter" by pressing the + button.

I added my own local interpreter xampp\php\php.exe Press apply and okay and go back to Languages & Frameworks -> PHP -> Test Frameworks and go for the refresh button. It should do some magic and then it will say PHPUnit version: 6.5 (or whichever you installed). I had my local (XAMPP) Apache server running.

In my case Comodo Internet Security (CIS) was adding php.exe to blocked applications.

Unblocking it fixed the issue.

My config:

• PHP 7.4.5 64 NTS
• Windows 10 1909
• PhpStorm 2020.1

[brad@T540p php-5.5.38]$ sapi/cgi/php-cgi -c /brad/home/PHP-Versions/php-5.5.38/php.ini index.php
X-Powered-By: PHP/5.5.38
Content-type: text/html

I did it!
[brad@T540p php-5.5.38]$ 

So, go download the php version you want. Uncompress the source. Go into the directory with the source files.

./configure --with-config-file-path="/home/brad/PHP-Versions/php-5.5.38"

make

cp php.ini-development php.ini
cp php.ini-development ./sapi/cgi/

The first php.ini is the one you specify in the ./configure and I used with the -c switch on the command line. However, PHPStorm seems to find the sapi/cgi/php.ini configuration... whatever, I don't care, it works.

At that point you should be able to point PHPStorm at .../php-5.5.38/sapi/cgi/php-cgi and it will recognize it locally without actually installing this version of PHP it into your machine in the usual places & configurations.

Since I wanted PHP v5.5.38, I named my directory php-5.5.38 as noted above. You may need to make adjustments if you have other preferences on naming your directories otherwise.