@2017,
It is doable to upgrade the PHP version by just renaming existing /xampp/php??? to phpold or something and dropping in new PHP directory tree using same directory name as replaced version. Then copy the php.ini from old version into new.
- Ensure you run phpinfo from your xampp control panel and get the same bus size and tread safe version PHP as previous install. i.e x86 non thread safe.
- I’m not sure what apache version is installed so note that as well. Hopefully it is at least 2.2.
If this doesn’t work then backup xampp somewhere then uninstall via windows uninstall(not directory delete) and install a newer version xampp. After which copy your my.ini and php.ini from old version.
Tedious but worth the upgrade if I say so myself
Edit: You may have to update your Redistributable for Visual Studio to correct version for new install.
Last edit: Are you going to upgrade from 2017 to 2018 soon?