Help needed, files dissapear after copying to WH Home Duo

Hi all,

i have the following issue (sorry for my english and any misstyping, its not my mother tongue):

The Home Duo worked very well for several weeks but now:

When i copy some files from my Desktop PC to my Mycloud Home Duo (16TB, Raid config) its copying just fine and finishes it but after a few seconds the file is dissapearing and i cannot open it any more.

Any ideas what i can do? Very frustating. A new install of WD Discovery didnt help

Please check this KB Article as it may relate to your issue.

Thanks for you answer. I deinstalled Bitdefender and did a test. it worked. but when i try to add the discovery software to the bitdefender exceptions the problem is still there

What i can see is that the files are disappearing but my free space is getting less so they should be anywhere.

best regards,