02-15-2015 06:01 PM
The following info may or may not help someone else with similar issues to myself.
I used the suggested formatting tool SD Association's Formatter from this thread and also selected the Format Size Adjustment option as ON with a quick format.
My card was then recoqnised in my Android devices (Toshiba AT300 & Samsung Galaxy SII).
The tool had set the file system back to exFAT.
Here is a snippet from the tools manual:
Format Size Adjustment
03-11-2015 10:50 AM
After searching all over the net and many failed attempts to format my 64GBsdXC it brought me to this thread. I have had this card in a netbook for 6 months but then I decided to use it as my media storage for my GALAXY S5. In the last week every time I tried to copy/add or erase delete any pictures or music card would look like it was done but files would return. Today I took it out and decided to manually move the media and that's when I noticed that files just reappear after. So I decided to Format the card with it inserted into the SD card adapter to no avail. And now here I have a card that is practically year old and now a dead weight. I guess I'll just avoid purchasing SanDisk after all these years as a loyal customer. Such a disappointment.
03-12-2015 07:52 AM - edited 03-12-2015 07:52 AM
Or you could simply call SanDisk and have it replaced under warranty.
03-17-2015 06:05 AM
It seems the ultra series of cards have a very high failure rate. When they fail, they go into read only mode so that the existing data can be retrieved when it fails. I would not suggest storing sensitive data on these cards.
Fortunately they come with a lifetime warranty from San disk. I just rma'd a 64GB ultra and they sent me an Extreme series. Hopefully more reliable.
One thing that irks me about this industry is that they get away with false advertising so openly. The 64GB card only has 59GB capacity. Without explanation I might be inclined to say it is a reserve for bits that go bad in the future but no. They have arbitrarily redefined 1GB to 10^9 instead of 2^30. I hope they next time the ceo of SanDisk goes to the grocery store and buys a dozen eggs the container will only have ten and the one pound steak will only be 10oz because the supermarket redefined what a dozen and a pound is.
03-17-2015 07:34 AM
Here's the explanation:
And it's NOT false advertising. And it's NOT just SanDisk.
03-17-2015 03:48 PM
I tried the various methods to format my 64GB Micro SD card described here, but none worked on Windows XP, Vista, or Win7computers. Not using USB or SD card slots. Not using SD Formatter. I tried all combinations of FAT32, NTFS and exFAT. They all only detected a physical size under 32GB. Typically 26.5GB
I then entered the 64GB Micro SD card into my digital Panasonic Lumix camera and it detected 58.5GB and formatted it using exFAT file system in seconds!
03-25-2015 11:46 PM
I too have the same problem with Sandisk SDXC 64GB memory card like the post by MORTALLKOMBAT.
I'm sick with it now. It manifests strange problems...I take pictures and few minutes to few days later, the new pictures I took is gone. Or the pictures I took 99% of the images are grayed out. I got so angry, I formatted it using the phone formatter.
Happy thinking some inconsitencies cause the proboblems are gone after formatting.....NOOOOOOOO!!!! Pictures are gone again. I am in the last leg of my vacation. I took bunch of pictures and they are GONE!!!!!! Only old pictures dates back 1/20/2015 are hanging around. Get this!!!! AFTER FORMATTING, NEW PICTURES ARE GONE AND OLD PICTURES COME BACK!!!!!!! HOW IS THAT PISSIBLE????!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I've been fighting this problem since 1/20/2015. Now 3/25/2015. I lost the pictures over 2 months worth. Vacation pictures/videos gone!!!!!!!!!
I also formatted the card using Win7 with USB connected. After restarting the phone, new pics gone and old pics come back.
The card is around 1/2 full. WTF SANDISK????!!!!! Even if Sandisk replaces with new one, I'm afraid to have the same problem!!!! You know??????
06-17-2015 10:10 PM
I came here with the same problem. I bought two 64Gb Sandisk MicroSDXC cards with adapters. Firstly, the fit of the adapters is horrible, which is probably a big reason for the failure rate. I don't have any devices that use the microchip directly, so I had no choice. It shouldn't matter.
Neither of my Nikon cameras, a D5100 and a Coolpix S32 could read or format the card. My Mac Pro desktop could see the chip, but couldn't format or write to it. It reported read only mode. I even tried an external 3rd part SDXC reader to see if that would make a difference. Nope.
I took the cards to work and tried on my 64bit Win7 machine. Nope, same thing. Tried on my iMac and got same problem.
Came here, and downloaded the SDFormatter - same problem - chips are read only. Couldn't do a thing with them. I almost gave up. But then I remembered that my Macbook Pro laptop (from 2011) had an SD card reader built in. Can't recall ever using it. Popped a card in a voila - it read the card and allowed me to format using the Apple Disk Utility.
After that, both cards now can be read and written to by both cameras. But, neither camera can format the cards.
It's really weird. I don't know that I can trust them.
06-19-2015 01:12 PM - edited 06-19-2015 01:14 PM
I've had the Sandisk Ultra 64GB Micro SDXC for over 3 years now. Bought it for my Note 2 and it worked great for the first year then the card got corrupted and I had to RMA it 2 years ago. That worked for a little under 2 years then it corrupted again with unable to format and I RMAd it again. This time however my luck seems to have run out.
When my 2nd RMA card arrived I popped it in my Kingston SD card reader and after transferring some files it just froze and couldn't be ejected and eventually I just unplugged it and tried again. Same issue it kept freezing while transferring files so I tried to format the card and was given the error that Windows was unable to format. I tried plugging it into my Macbook and it couldn't format on that either so I asked for an RMA again.
Now with my 3rd RMA card, SAME ISSUE but this time I bought a brand new SD card reader (Transcend SD Card Reader) and still the same issue almost immediately. It froze when transferring files and card is unable to be formatted. I ried other SD cards to see if it was a reader issue but those SD cards (Sandisk, PNY, Generic) seem fine but they were smaller capacity and none SDXC and all those read fine on my phone and readers. I was able to format each of those successfully as well so the issue definitely seems to be with the SDXC.
So today I contacted Sandisk for my 4th RMA and I was promised an upgrade to the Ultra Plus line but honestly at this point I don't even think that'll work. I've tried using various different phones, readers and computers and they all seem to have the same issue with this card. I'm really not sure what to do if my 4th RMA fails again.
I tried various formatting programs as well including SDFormatter V4.0 and absolutely no luck with anything. I'm not sure if this is a Sandisk issue or just a general SDXC issue but what I do know is that I am slowly losing faith in their products. However on the bright side each and everytime I have contacted their support, they have been of utmost help. I've had a very pleasant experience each time however I wish their products would reflect their customer service.
06-24-2015 07:13 PM
I've been there. there is no problem with the operating system you are using. it is because the SD card gets problem.
there are quite a few solutions I found online and I believe there must be at least one that can fix the problem, such as format it at Disk Management, using command line or check and repair bad sectors.
For me I prefer buying a new SD card, as SD card can't be completely repaired. (One of my friends whose work is repairing computer told me).