I got a flat :( (Disk Fault WD4100 MyCloud 24TB)

Do you have a PR4100, DL4100 or EX4100? Calling it a WD4100 is meaningless, and you don’t have long because if another drive fails you’ll lose all data.

The first step is to determine the condition of the existing drives, which can be done by installing the Get S.M.A.R.T. app from the list below, then running the app and posting the results.

My Cloud OS5 Apps Matrix (Third-Party)