Cannot read SD Card in Oscar?

[Tman1966]

My Resmed 11 stop transmitting (apparently a 3G cellular issue). I learned about Oscar on this forum. My understanding was any SD card would work, so I inserted a SanDisk 64GB. Upon insertion, the CPAP device appeared to see the card and the LCD said it was "formatting card." So far, so good. Then, a month goes by, I take the card out to look at the data, insert into a reader for my Macbook (running Ventura 13.6). I get an error message saying the laptop "does not recognize the inserted card." I made sure the Privacy/Security tick box for "Allow Accessories to Connect." It still did not work. 

Any ideas why this is not working? 
Thanks

[eok361]

so you did the formatting via your machine? if so, maybe try formatting it first on your mac, then plugging it into your machine. 

i'm not a mac guy, but in either event i would try that. if you can at least get the data off the current card to your hdd before reformatting, try that. 

if you're afraid of losing all that data, and there's a way to recover it, then try another sd card. 64gb may be beyond what the machines can write to. i have a 32gb sandisc ultra plus, and have no issues with my as10 or oscar. but again, that's on a pc.

good luck.

[SarcasticDave94]

Was this SD card formatted to FAT32? As I recall, the 10 series ResMed might not have accessed a 64 GB SD card, but I thought I'd seen the 11 series can.

[Crimson Nape]

I recall the Macs don't do well formatting a FAT32 on SD cards.  The SD Association has a free app to take care of this.  If the card is larger than 32GB, I believe the AS11 will read the exFAT format.

Here is their link:  https://www.sdcard.org/downloads/formatter/

- Red

[somewherein413]

I am not as knowledgeable as most on this thread. But I get a similar error message from my PC but if I go into OSCAR it will read the data when I point it at the drive. This is in Windows, but I thought I would put it out there in case it works for you.