SDXC cards exFAT only. why not NTFS?

I'd try Rufus.

If it's unreadable then I'd look into whether Hiren's boot cd (usb) has anything useful. Otherwise it's likely not recoverable unless an expensive specialist service can do it. If the client wants the data no matter what the cost then don't do anything other than send it to a specialist service.

It's actually 'offered' in the formatting options, but never completes successfully. It tells me so, and the result is a RAW disc. Quick exFAT format gets the card back again.

I'm told that some cards are also device-specific.

RL

Not trying to recover somebody's old cam data.

Looking for simple NTSF volumes for large data (small files) physical access between older non-exFAT machines.

I have one that formats as NTFS, but corrupts eventually, when data is written by older machines. Files and folders are visible under explorer, but are rubbish, when accessed.

Haven't tried it with a 'reputable brand'

RL

They are strange animals.

One, which produced a flakey NTSF format has a 1.5MB invisible disk usage.Disk management identified it as having an MBR.

I'm checking out what a 256GB part ($50 with mfr and warranty) will do when used as intended. NTSF no obvious problem, so far.

The 516GB cards giving issues were an order of magnitude or two cheaper. ie junk.

RL

Did you try the offical formatter?

Wonder how serious they can be, without offering something aimed at Linux?

( well . . . none of the formats addressed are open source. )

RL

I mapped a tar device onto a sdcard. In practice you could allocate a file and write a sequential image with no overhead, just sequential blocks like on a tape. The advantage that it is actually in practive a random access device and you could e.g. read a part of a disk video. There are no clusters are some idiocy, and the capacity is not limited to 160 kbyte then 32 Mbyte then 32 Gbyte like Microsoft. Groetjes Albert

Alarm bells ring. Are you sure those 512GB cards are actually 512GB, or are they 'Amazon 512GB', which means a fake small card that pretends to be

FAT (I can't speak for exFAT) is good at masking fakes because the FAT table is in a fixed position. The faker can ensure it's always on real flash and so it's just file data that disappears which you don't notice until later (hopefully after the seller has done a runner with your money). Other formats put metadata in different places and if that gets thrown away by the fake card then things may fail a lot earlier.

I'd do a test with a tool like h2testw and see if the card checks out:

Theo

I tried it, after your suggestion.

ONLY option is exFAT.

RL

The SD Card org SD Card Formatterv v5.0.3 was in question.

For one specific SDXC card, NTFS formatting could be achieved using native W7 format options in the GUI (but not using the .org's programme).

The same native formatting wasn't an option for two other SDXC cards under examination. .org's formatting program was uniformly single choice.

One card that could be formatted in both exFAT and NSTF by W7 failed h2testw testing, regardless of formating type. I stopped testing after

RL

Someone else pointed out that you've probably got an "amazon" card there. One which reports to the operating system that its size is much greater than it really is. This will show behaviour exactly as you describe. I've seen and tested these fraudulent cards myself.

I got a phone call from someone who sorted out a refund after I sent the defective devices back with an explanation of what they were.

All three tested so far corrupted/lost data above 30G.

All three 'Moric' brand 512G.

They seem to have successfully buried a few Reddit reports of the fraud under a slurry of single-sourced web advertizing, for anyone researching the product on the interwobble..

Amazon sales seem to be stopped, but not e-bay.

RL

Why would you want to beat your SD cards to death by formatting them as NTFS? I hope you at least choose a large file allocation block size.

There are alao USB memory sticks (30G and 60G) that fail to start testing when NTSF formatted, but test clean when formatted as exFAT.

RL

My machines are not networked,(most have no internet connection) but all benefit from access to a large library.These don't get a lot of changing data - just incremental updates.

This has been achieved in the past with hard drives in removable caddies, or external usb hard drives (iffy in older machines with lower usb power delivery).

They can all read low-power large-volume ntfs-formatted memory cards.

So far the library will just fit a 256G part. 516G is therefor preferred.

RL

None of the external USB HDD I've got have a discrete power inlet.Usual trick is USB split connector (2xUSB power) with one that has power-only connex. You could use a USB expander with a wall wart, but this just adding to bits and pieces.

I'm trying to retire plug-in drive caddies. Too many mech issues with aging hardware and no resources for new stuff.

None of the windows or linux boxes here have trouble with ntfs.

If it works reliably, an SD card should be the smallest, simplest and cheapest option. None of the file sizes are more than 56M, but I shouldn't expect it to choke on the occasional large RAW data file, when travelling.

It takes a working day + (or night) to write (or to test) the whole thing.

RL