If you try to connect your Samsung Galaxy S6 to the computer and sync with the Samsung Kies 3 software or to make a backup, then this will not work anymore. The reason is the following:
Samsung's Kies 3 no longer supports the Samsung Galaxy S6 and the Samsung Galaxy S6 Edge.
Instead of Kies 3 Samsung has introduced the software "Smart Switch".
SmartSwitch is identical to Samsung Kies, but you must first install it on your PC.
SmartSwitch can be downloaded from the official Samsung website:
The file is about 37 MB in size. After installation on your PC or MAC, your Samsung Galaxy Galaxy S6 or Samsung S6 Edge can easily be connected to your computer via USB.
After you have connected the Samsung Galaxy S6 via the USB cable the software Smart Switch automatically detects the Samsung Galaxy S6 and gives you all the options on the screen.
You know now why the Samsung Galaxy S6 can´t be connected with the software Samsung Kies 3 and what to do to solve that issue.