Samsung T7 on Mac and Windows: formats and fixes
The Samsung T7 is a popular portable SSD for Mac users. Out of the box it works on both Mac and Windows. It stops working on Windows when someone erases it on a Mac in a Mac format.
What Samsung says
From the T7 user manual (checked October 30, 2026): "T7 is pre-formatted in using exFAT file system which is supported by Windows OS, Mac OS, and Android operating systems." Its table of file systems:
| Format | Windows | Mac |
|---|---|---|
| exFAT | Both read and write | Both read and write |
| NTFS | Both read and write | Read only |
| HFS | Not recognizable | Both read and write |
Samsung's table does not list APFS; Windows does not read it either. What is APFS
Write-locked after using it on a Mac
Samsung warns: "When using exFAT across multiple operating systems, data writing may become locked and you may only be able to read data." Its fix on a Mac is to "Connect T7 to your Mac again, and perform Eject". This is an exFAT issue; the files are readable.
Reformatted as APFS or Mac OS Extended
Many Mac users erase the T7 as APFS for a Mac-only workflow. On Windows it then shows no files and Windows may offer to format it: choose Cancel. Diskferry reads it read only: Find Mac drives, browse and preview for free, then copy with verification.
If the T7 has Samsung's password protection turned on, the manual says access is "confined to capacity of about 128MB" holding Samsung's unlock software until you unlock it. Unlock it with Samsung's software first; Diskferry cannot unlock it.
Questions
Which format should a T7 have for Mac and Windows?
exFAT, as it ships. Use APFS only if the drive never needs to be read on a PC.
Last updated October 30, 2026. Still stuck? Support replies in person.
Related guides
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- WD My Passport for Mac on Windows: read it safelyIt ships formatted for Mac; how to get files off it on a PC without erasing it
- How to open an APFS drive on WindowsAPFS is the Mac format since macOS 10.13; Windows needs help to read it
- Diskferry comparedMacDrive, Paragon, TransMac, HFSExplorer and the free options, with sources