MacOS/Windows - Can't access data from external hard drive

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The external hard drive is a memory device used to store data and other multimedia information on the hardware. This is generally used as a portable hardware to be carried along when travelling or when the PC's internal memory falls short. An external hard drive may be compatible with multiple Operating Systems. However, sometimes you may face issues where your PC is not recognizing the hard drive. If your PC has both MAC OS and Windows operating systems, in order to make the HD work, reformat the HD along with FAT32 file system. Reformat the hard drive disk with "Disk" to enable all functionalities regarding formatting of a hard drive disk.


I have just bought a 100GB external hard drive. Please help me as I am a novice. The hard drive was advertised as being useable on both, Mac and PC. I have both - Windows XP and Mac OSX. My PC doesn't recognize the HD at all. Mac does but when I try to drag files on it I get this message: "... cannot be moved because... cannot be modified". Can anyone help?


  • Reformat your external hard drive with FAT32; after that it will work on both Windows and Mac OS. To format the hard drive please follows the following steps:
  • Open Finder
  • Click Applications
  • Press, u on keyboard. If Utilities is highlighted, click it. If its not highlighted find it and then click it.
  • Click "Disk"
  • Disk is the app to use for creating, restoring, raiding, erasing & partitioning either your internal HDD or External HDD.


Solved by Msk7
Jean-François Pillou

Jean-François Pillou - Founder of CCM
Better known as Jeff, Jean-François Pillou is the founder of He is also CEO of CCM Benchmark and digital director at the Figaro Group.

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