Error code 4

hi, i have a ex4100 with 2 wd red hdd 6 tb ( volume 1 raid 1) in bay 1 and 2. all it is ok. I decided to buy 1 wd red hdd 4 tb.
I inserted the new hdd in the bay. when the start process is finished the led light under the 4 tb drive is red while the start ligth is blu and the two led under the 2 hdd 6 tb are blu. Thank you for any help

Hi ang1,

You have to login to your My Cloud dashboard. Here, you should have a notification that a new drive has been added. Then set it up as a new JBOD volume.