Hello,
since a few weeks i have the problem that my "KindleforPC" cannot establish a connection to Amazon. 

The support tells me, i must install the Kindle app from the Windows Store.
In this app the ebooks are stored in the directory:
C:\users\username\AppData\Local\Packages\AMZNMobil  eLLC.KindleforWindows8_stfe6vwa9jnbp\LocalState\ca  che\
Each ebbook has its own directory with hundreds of files named "1.fragment", "2.fragment" and so on.

Calibre is not able to import these fragmented ebooks. 
What can i do to add and use my ebooks in calibre?
Greetings
Ralf