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I currently have an external, HFS+ drive as my time machine storage that backs up my Macbook Pro Retina (Mac OS Mountain Lion 10.8.1). I also have another external NTFS drive (that I share with my Windows Desktop) which has all my photos etc which I would like to backup via Time Machine.
Macbook Pro Retina ===> external Time Machine drive
Macbook Pro Retina ===\ +====> external Time Machine drive External NTFS drive ==/
If I go into the Time Machine preferences, I see the external NTFS drive (as well as all other NTFS/HFS+ drives) inside the exclude list. I can also remove the NTFS drive of interest from this exclude list - thereby including it into the backup list.
The problem is that the settings aren't sticky. When I reenter the Time Machine preferences, the external NTFS drive is again seen on the exclude list. And the actual files themselves aren't backed up either.
So, how can I backup the data on my external NTFS drive via Time Machine?