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Help Micro SD card help plz

Greetings and salutations

I'll keep this as brief as I can. I'm having an issue with my micro SD card for my xperia. Its a SanDisk sdxc 64 gb. I had it for 4 months and all of a sudden Im unable to copy or move files to it from my phone. I can't delete files or even format it through my phone or my laptop.

If I delete a file the file will appear to have been deleted, but when I restart the phone the file will reappear.

However the files that are currently on the card are fine. Meaning i can listen to any audio file or view any video i have on the card. I just can't delete any files or add any files.

I would appreciate any help or advice on what to do
 
I just did that and everything checks out

It displayed the manufacturer, the size and the serial number

Unless you wanted to look for something specific?
 
Take out the card and look at it carefully. Some microSD cards have a little switch that will write protect the thing.
 
I looked into that but no switch like that exists and plus the card was fine and I never pulled it out. It just suddenly happened
 
Sounds like the SD itself has switched to read only mode, which is something they can do if they detect they're starting to fail. Basically to try to preserve and protect the existing data on there. If you've only had it four months, it should be under SanDisk warranty for exchange.
 
Is there a fix for this because I don't want to go through the warranty process. Like changing its format to fat32? Or something
 
If it is failing or defective, and so gone read only by itself, there's nothing you can do with it at all. I had a USB flash drive go read only a few months ago, although I had been using it daily for a couple of years, and had basically worn out. Can't reformat it, because the whole thing is now read only. It's a diagnostic in the flash controller chip itself that does it, and no way for a user to change it AFAIK. And even if you could, I certainly wouldn't go relying on a suspected defective or faulty storage device.
 
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Is there a fix for this because I don't want to go through the warranty process. Like changing its format to fat32? Or something
The odds are that your 64GB microSD card was already formatted as exFAT (default FAT32 partitions are limited to 32GB which includes a limit of individual files at 4GB). The industry standard for SD cards is FAT and that itself is probably a factor in your problem. The FAT (File Allocation Table) file system is dated and not very expansive. It's not uncommon for microSD cards to become corrupted and problematic because their underlying file system just isn't as reliable as it could be. (There's no shortage of postings here in Android Forums specifically about microSD card problems.) Years ago the USB standards board (USB-IF) settled on using Microsoft's proprietary, limited FAT as the default standard file system, instead of any more flexible, open, and unencumbered file system. That decision created the FAT-related limitations we all must cope with now.
https://en.wikipedia.org/wiki/USB_Implementers_Forum
Instead of FAT32 you might want to think about formatting your next microSD card as ext4, the default file system your Android phone uses. Then both your phone's internal storage and microSD card will be in parity. (Although this solution applies if you leave your card inside your phone. If you periodically remove it to transfer files between your phone and your computer note that only neither Windows nor OS X include support for ext file systems by default, you need to install a third-party utility.)
 
The odds are that your 64GB microSD card was already formatted as exFAT (default FAT32 partitions are limited to 32GB which includes a limit of individual files at 4GB).

I beg to differ on that actually... :)

2tb.jpg

That's a 2TB hard drive formatted as FAT32, single partition. I done it like that because that's all my not-so-smart, Konka TV with USB can deal with for viewing movies and TV shows from the drive. Can't use exFAT or anything else with it. But indeed it is limited to 4GB maximum file-size, but that's not a problem for my uses with it. And I've also formatted 64GB SDs as FAT32, and not had any problems with them in Android devices.[/QUOTE]
 
OK I can't really argue that point but in my defense I did intentionally include the word 'default'. The default maximum partition size for FAT32 stated by Microsoft is 32GB. It was a suitable size for its time but once that became an issue that's why they cooked up exFAT. But whatever the case the basic problem that we're all stuck with is the fact that SD card implementation opted to follow USB's implementation, a limited, dated file system.
 
FWIW I formatted the 2TB external USB hard drive as FAT32 using a Mac, so don't think Microsoft approval really came into it. :) It originally came from Seagate as Windows NTFS. Which was pretty useless for my needs. Mac OS X can use exFAT, but my TV can't. Same thing for >32GB USB flash drives as well.
 
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Is there a fix for this because I don't want to go through the warranty process. Like changing its format to fat32? Or something

NO! If you format the card, you will lose everything on it! Since the card is legit, it is - as noted previously - probably about to fail. I advise you to immediately copy the card's contents into a folder on the PC and get another card. You can buy one outright and THEN start the warranty process. You'll end up with a spare card, but that's not necessarily a bad thing. But the more you access the card, the faster it will ultimately fail. Back it up now.
 
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