For the last two months Time Machine has been successfully backing up my MacBook Pro to my WDMyCloud Drive. Then after the 2.11.133 Firmware update I started to have problems. First it forced me to create a new backup to replace the original one. Now for the regular scheduled backups its telling me It can not write to the drive. I can read and write files manually to the drive, but the Time Machine backup operation always fails now. I ran all the diagnostics from the Dashboard/utilities and the rebooted the drive twice. I contacted apple support and they ran some tests. They said my computer is working correctly and said I should contact WD for help. I also backup up 3 other window based machines over my home network to the same WDMyCloud drive and haven’t had any problems. Is there a fix for this or can I back-out the firmware update? Is anyone else having this problem?
On this case, try to reset the unit to see if this helps, please check this link in order to get help on this process:
Also try contacting support to see if they can better assist you on this matter: