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HDD Drive Suddenly Became Read-only after Installing Windows

After I followed the directions in a guide article to install Windows 7 on my HDD drive, the drive became read-only on both OS X and Windows. It's formatted UDF (and I have MacFuse anyway, so it wouldn't matter if it was NTFS). I want to make the drive workable again, even format and reset it if needed. What should I do?

Best Answered by

Connie Yang

Answered on Tuesday, August 27, 2024

The UDF file system is the industry-standard format for the DVD optical media. Although you use MacFuse to enable macOS to work with the UDF file system, your UDF-formatted HDD may still perform improperly.

To make your HDD can be read and written, you have no choice except to reformat it to another file system on your Mac.

  1. Open Disk Utility and let DU finish loading.
  2. Select your drive and click Partition in the DU main window.
  3. Choose the number of partitions from the drop menu to one.
  4. Select the format to Mac OS Extended (Journaled), and set the partition scheme to GUID > OK.
  5. Click on the Partition button.
  6. Choose the volume you created just now and click Erase in the DU main window.
  7. Set the format to Mac OS Extended (Journaled) and follow the on-screen guide to finish erasure.

This process may take some time, don't interrupt it.