Accessing fat16 partition on windows11

I have an old PC clone with an XT-IDE and compact flash card. I created a partition with FDISK, and can successfully boot off of/use the CF card on the pc clone.

What i want to do is load files on to the CF from my modern windows PC. That is where the trouble starts.

When I explore my CF in windows (via a usb/cf drive), it shows up as blank. When put files on the “blank” drive, they don’t show up on the old pc clone. Clearly, there are separate partitions going on here. And each respective computer only sees one (different) partition.

I have no idea how it would have 2 partitions. I just took the fresh CF card and used FDISK on the clone and formated it.

Googling seems to imply that Windows 10 and up only handles fat16 (lba), which maybe explains why the two computers don’t see the other partition? Maybe?

Here is a screenshot of Windows Disk Management showing the CF card in question. I believe the 125 mb partition is the one Windows sees, and the 28 mb one is the one dos sees. I can’t do much with that partition without Windows throwing up a cryptic dialog saying i need to refresh Disk Management or restart. No dice.

(Addendum): what happens if I change the partition table entry of the small partition to say it’s an lba partition? To trick the windows pc?

I found this on the MS support

Windows 10 indeed formats FAT16 differently from previous versions. I had a issue where an old device would reject Windows 10 FAT16 formatted cards while accepted Windows 7 and earlier FAT16 formatted cards.

The difference is that, assuming you are using a MBR partition, Windows 10 formats FAT16 leaving the partition ID as 0x0E and Windows 7 and earlier leaves the ID as 0x06

If you want to change the partition ID of a MBR FAT16 formatted disk to 0x06 you can run PowerShell as administrator and run the following code:

Set-Partition -DriveLetter X -MbrType 06

Where you replace the X in -DriveLetter for the correct drive letter of the disk you are trying to change the partition ID.

Otherwise I would check this in linux. (including formatting the partition there)

1 Like