Same problem here. I think the network interface in the MBL is shot. The lights on the drive still light up on the front and the back but I can’t see the drive on the network. When I go in to my router settings, I can’t see the MBL as connected to the router. I even isolated the drive as the only wired device connected to the router, and the router showed no wired connections.
It seems that the network interface started to fail a few weeks ago. I was transfering a large volume of files to the drive and left it overnight. It ended up failing about 3/4 of the way through. After that, computers on the network were having issues connecting to the share. Sometimes I could connect, other times I could not. I went away on vacation for two weeks and when I first returned I could still see the base shares. Now nothing. When I was still able to connect to the drive, I noticed some folders, with files, missing. I didn’t know if the issue was related or the files were really gone. Now without being able to connect at all, I really don’t know the status of the files.
I was initially thinking the problem was because I had setup a static IP address on the MBL when it was connected to our old router. I can’t remember if I changed it to Dynamic when we got a new router. Though I must have because I was able to access the drive through the new router for several months. It just seemed to stop working consistently in the middle of that night of the big data transfer.
I have done a lot of searching. I have power cycled the drive and the router. Changed the network cable. Used the little reset button on the back of the drive. Nothing seems to work. Searches have turned up nothing and no one ever seems to post a resolution if they found one. I think the only option may be to pull the drive and connect it to a Linux box.
Thankfully I started using OneDrive earlier this year and transferred most of our working files there except photos and vacation videos. Though I have a backup of those. I am just concerned about some missing 2018 receipts because the last full copy of the drive I did was about 12 months ago.