How To Fix Mac error code 1309

How to Fix Mac Error Code 1309: A Step-by-Step Guide

Mac error code 1309 typically occurs when attempting to copy large files (over 4GB) to an external drive formatted in FAT32. This error arises because FAT32 has a maximum single file size limit of 4GB. To fix this issue, the external drive’s format or file permissions often need adjustment. This guide provides clear, easy-to-follow steps to resolve error 1309 on your Mac efficiently.

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Step 1: Verify the Format of Your External Drive

• Connect your external drive to your Mac.
• Right-click the drive icon on your desktop or in Finder sidebar, then select Get Info.
• Look under Format to check if it says MS-DOS (FAT32).
• If the drive is FAT32, this is likely the cause of the error because FAT32 cannot handle files larger than 4GB.

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Step 2: Backup Important Data from the Drive

• Before reformatting, make sure to back up all important data from the external drive to another location.
• Formatting will erase all data on the drive, so backup is essential.

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Step 3: Reformat the External Drive to a Compatible Format

• Open Disk Utility by navigating to:
  Applications > Utilities > Disk Utility.
• In Disk Utility, select your external drive from the left sidebar.
• Click on the Erase button at the top.
• In the format dropdown, choose one of the following based on your usage needs:
  • exFAT (compatible with macOS and Windows, supports large files)
  • macOS Extended (Journaled) or APFS (if using the drive only with Macs)
• Name the drive as you like and click Erase to reformat.
• Once completed, your drive will accept files larger than 4GB without error 1309.

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Step 4: Check and Adjust File Permissions (if error persists)

• Locate the file or folder triggering the error.
• Right-click the file/folder, select Get Info.
• Scroll to the Sharing & Permissions section.
• Ensure your user account has Read & Write access.
• Click the padlock icon to authenticate and modify permissions if needed.
• This step helps if the error is caused by permission conflicts rather than file size limitations.

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Step 5: Run Disk Utility First Aid on Your Drive

• In Disk Utility, select your external or internal drive.
• Click First Aid and then Run.
• This scans and repairs any disk errors that could be causing file transfer issues.
• Wait for the process to complete and retry your file copy operation.

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Step 6: Clear Temporary Files and Cache (Optional)

• Sometimes error 1309 can be influenced by system cache or temporary files.
• Use a Mac cleaning tool or manually clear cache files:
  • Open Finder, then Go > Go to Folder.
  • Type ~/Library/Caches and delete non-essential cache files.
• Restart your Mac and check if the error persists.

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Final Tips for Avoiding Error 1309

• Use compatible file systems like exFAT if you work across macOS and Windows.
• Keep your Mac’s software updated to avoid compatibility bugs.
• Ensure files are not corrupted prior to transfer.
• Consider alternative file transfer methods if issues continue, such as using Cloud storage or AirDrop.

By following this guide and reformatting your drive appropriately, you should be able to successfully fix Mac error code 1309 and transfer large files without interruption. This ensures a smoother, error-free experience when working with external storage on your Mac.