bollenboer wrote:Does an updat version excists for Xampp 1.8.2 to a newer version ?
No.
bollenboer wrote:If not : how can I install the latest Xampp version without losing my running websites ?
You cannot.
You can only make a full backup of your Xampp Installation (do NOT use the Xampp Backup facility, it does not work!!); simply make a copy of the whole Xampp folder. Also make a backup of your MySQL Data, use PhpMyAdmin to export the data into *.sql files.
Then deinstall the old Xampp, install the new Xampp, restore all your websites and restore the MySQL tables. And keep in mind, that you might have changed any configuration files (i.e. for VirtualHosts, for certain Modules in Apache or PHP etc.) and apply these changes to the new config files (if necessary). It is quite a task to do an upgrade to Xampp, that is due to the fact, that Xampp is not "one software", it is a collection (i.e. distribution) of many different products (from different developers) and only comes preconfigured to run out of the box. There is no update/upgrade procedure, as it is to hard to adapt all the user changes.