I have multiple partitions and my last partition regularly disappears

There are two workarounds for this phenomenon:

  1. Only use one primary DOS partition.
  2. Using FDISK, follow the steps below when partitioning the drive:
    1. Create a primary DOS partition with the desired size.
    2. Reboot
    3. Create an extended DOS partition using 99% of the available space remaining instead of 100%
    4. Reboot
    5. Create as many logical DOS drives as required, but with a reboot between each logical drive created.
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The Benefit Of Creating Multiple Partitions In Windows

With current drive technology, you are unlikely to notice any increase in performance by creating multiple partitions on the drive. One real benefit of doing this is that it decreases the amount of time that ScanDisk and Defrag take to complete. Also, if you store data on a secondary partition and for some reason need to reformat the system partition, you can do so leaving your data files on the secondary partition intact.

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