Smo) If ejecting or unmounting the backup drive doesn't fix the problem, the Time Machine volume may have disk errors that need to be repaired. To unmount the volume, start by accessing the disk utility. 5% of volume size for MFT and does not allow writing there any user's data, which lets MFT to grow. You cannot use a volume that is included in the backup as a storage location. This volume cannot be used because it is a backup disk If the volume that cannot be recognized by Windows is on external HDD, memory card or USB flash drive, you need to connect it to computer and make sure it can be detected properly.
