So here’s the deal: The answer given here and the info at the linked pages in the answer don’t reflect how the product actually works.
Two years after the original question from the original user, I’m having the same issue.
Here’s the problem: I’m trying to use Acronis True Image 2020 for Mac to backup my computer to WD My Cloud Home. The True Image app sees the My Cloud device as a target for the backup. When I select it, what looks like a Mac OS message appears: “To access the location, enter the login and password.” Radio buttons let me choose Guest or Registered user. I choose the latter, enter my WD My Cloud username and password, they’re accepted, and I’m in. Oops! Not yet. Next, I’m presented a small window – also the type generated by Mac OS for server sign-in – that asks me to: "Select the volume that you want to mount on NAS “MYCLOUD-xxxxxxxx” (x=identifying info). “Public” is the only Volume appearing in the list, so I select it.
And here’s the part that by your previous answer, you seem not to understand: The message appears a second time: “To access the location, enter the login and password.” Again Guest and Registered User are the choices. Selecting Registered User brings up the text entry boxes for name and password. Only this time, the same My Cloud username and password don’t work. Choosing Guest also doesn’t work.
Now, I don’t know if Acronis True Image is presenting that second login window, if the Mac OS is presenting it, or if the My Cloud device is causing it to be presented. But I suspect it has to be the My Cloud. And it is clear that True Image wants to write to the Public space.
So the question is: What username and password will enable True Image or the Mac OS to mount the Public volume so that I can proceed to send a backup file into it.
Please do not direct me to the same page as in the previous reply, because the answer is not there.
As an additional note: If I use True Image’s “Browse” option as another way to select the My Cloud device as a backup destination, I see the various folders I’ve created either in the My Cloud browser interface or in the Mac Finder through WD Discovery. These folders can be chosen, but backup to them fails. I assume that’s Acronis’s problem, not WD’s and I’ve written to them about that.
I have lost most of my weekend to trying to get My Cloud to do the things I want to do.