I have read your case Mona as well as numerous others. WDCloud nas comes with its own back-up system that you must configure from the start. Me, like most, just want to get into backing up/storing data. After loading the drive I noticed that when deleting, it kept referring to permanent deletion for every file. WTF, no recycle bin!
I looked into it further and tried setting up the "time machine back-up" etc. After a 'not enough room' error and then tried to set it up on the external usb device. This also didn't work and crashed the device. After rebooting the WD, I put it in the too hard basket until my accidental deletion.
I have since been lucky to recover 75 percent of my folder deletion using putty/unmount/extundelete as per all the instruction on this string of posts. I was also very lucky to find most of my original photos still in storage and can re-scan them bringing me back up to about 90 percent.
The critical key, as mentioned, is to turn the bloody machine off!. You leave it on and it will crunch away merrily with it own nas processes, and write over your deleted files. Only turn it on when you are ready to recover.
I consider myself lucky and thank everyone in this string for your help. I am sure we haven't heard the end of this...note. Still can't set the 'wd recycle bin'. It crashes the device and won't let me log in. So I am now removing data until I get this issue sorted...NTS...and everyone...Remember to backup!