As you know, Win 8.1 supports “Storage Spaces” or drive pooling which enables easy software raid mirroring and such for multiple storage drives. You can choose NTFS or ReFS. I chose ReFS as its a superior format and can self heal, etc. ReFS is the future and MyBook 4tb backup drive is incompatible with it. It can make a manual backup, and create a schedule or continues backup, but after that point, it never correctly adds NEW files as they are added to the source drive (which in a ReFS drive pool). This was confirmed with level 2 tech support.
I realize a small percentage of users are using ReFS now and its not a huge issue. But it will be in the near future - especially with Window 10 which will be out soon and they will be promoting “Storage Spaces” and ReFS more in the future. ReFS is the superior format and the WD backup drives should all be able to work with them. It is like having a software RAID 0 mirror that cant be backed up by your WD external drive. None of this information of incompatibility was displayed on the box, website, manuals or support information. It should be as I would have either not bought the drive or configured my system to be NTFS drive pool. Either way it needs to be addressed. The auto backup function is useless to me now. People will be migrating to ReFS heavily in the future because its superior for storage drives and Win10 promotes this.
Update process (second smaller complaint)
The WD software is really pretty poorly done considering the size of your company. Another anomaly is that it ALWAYS tells you that you need an update. Then to compound the issue, the build number displayed in settings will be only the first 3 sections - i.e. 2.4.10. It wont show the last section of the updated build number (i.e. 184.108.40.206) so you cant even see which build you have. No real excuse for the build number and update process being handled so poorly.