cagnaluia wrote:But I wouldn't to reinstall a different version of XAMPP because I'm worry about wordpress installation and mysql data stored.
There are two possibilities:
1. install a second XAMPP version side by side to the first one (there are some disadvantages if you want to run them both simultaniously)
2. add a second PHP version with CGI or FCGI (but that would be much more complicated than reinstall to migrate to a lower PHP version)
Dumping and restoring a webapplication including it's database is a base knowledge task so maybe you should try to learn this earlier than later.