Problem with WDmyCloud2Ex and FreeFileSync

Hey there
I have a Problem using Freefilesync and WDmyCloud2ex

While comparing the directories from PC and WDMC2ex I am Always getting this message:

Die Dateiattribute von \Wdmycloudex2\pc2013\pdfDruck](file:///\Wdmycloudex2\pc2013\pdfDruck)
koennen nicht gelesen werden.
Fehlercode 58: Der angegebene Server kann den angeforderten Vorgang nicht ausfuehren.

It’s in German but I hope you’ll understand this message.
FreeFileSync always wants to write a file named “sync.ffs_db” into the destination directory to compare
but WDMC2ex doesn’t allow this and sends an error-message back to FFS.

What I’ll have to do to connect FFS and WDMC2ex for comparing and sync?

For Information:
FFS is working without any problem for example compare and sync with external USB-Disk!
It’s possible to copy files from PC to WDMC2Ex without any problem!

Greetings from Germany