Here I had simply given up on the factory enclosure and a separate Acomdata model years back. From what I keep finding when looking at the numbers WD hasn't ever been able to get this problem cleaned up over the years since first models saw the same problems as you are now. I put a red mark on each side to indicate which one while the model information will identify which one anyways.
Once the drive is detected it appears on top. Here I will the drive in the enclosure with on/off switch turned off and only see the two OS drives and two storage/backup drives listed under Disk Drives until hitting the switch. One place of the two places you can look to see if there are any yellow marked items would be under the Universal Serial Bus Controllers section at the bottom as well as taking a look in the Disk Drives section. I also was finding data transfers were going much faster when 3.0 flash drives were on 2.0 ports instead of 3.0! The 3.0 bus simply provides more current to allow for 6 devices rather the limit of 4 seen with 2.0. I have several 3.0 flash drives recently added to the collection of flash drives here when 10 was first out that are plugged into a large 7 port 2.0 hub at times without any hiccups. Generally anything 3.0 will work on the 2.0 ports without any problems.
