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I am using 64GB micro SD-Card.

I always put it into my laptop slot for secondary storage.

Recently, I found a big problem that my SD card won't work properly.

I mean,

When I copy new files to the SD card. Firstly, it appears right. The file is intact and I can access the file. However, whenever I restart Windows 8 or when I wait about a few hours, the copied file is gone! just gone!

But the old files (before the problem appeared) still remained well.

Thus, I tested more. Amazingly, when I delete the old files that means the files that I copied days ago, it seemed to be deleted at first. However, when I restart my Windows or wait for a few hours, It re-appear! Wow...

That does not happen when I refresh the Explorer or press F5. I have to wait for a few hours or reboot my laptop.

In summary, my SD card seemed to be 'held' at a certain moment. Whenever I copy new files, they will be deleted. Whenever I delete old files, they appear again!

Does anyone know similar issues?

Thank you!

Windows 8 SanDisk Ultra 64GB. Class10.

I have another SD card exactly the same model of this one, and that does not have any problem yet.

I don't know whether it is relevant but this problem appeared about when I installed double-twist player. (but I never run this program after I acknowledged this SD card issue for sure)

share|improve this question
Have you tried copying a file to the SD card, safely removing the SD card from within Windows, then mount the SD card on a different computer? It may be an issue that the SD card isn't being properly written to and the file stays in the cache. – Kruug Jun 21 '13 at 16:47
@Kruug I just tried that. Deleted some files and copied new files to SD card. When I dismount and remount, new files are gone and old files re-appeared. So, I think you are right that operations are not being done properly. Do you have any idea? Thank you. – klados Jun 21 '13 at 17:04
@Kruug I just cross-tested the SD card, and figured out that the SD card is the problem. I used another SD card and it works well. I cross-put SD card into each slot and also the properly-working SD card works well in another slot. So, the problem is the SD card. Is there any option? or should I stop using that? – klados Jun 21 '13 at 17:06
Sounds like you have a bad SD card. Best bet is to stop using it. If it's a new(er) card, you may be able to RMA it if you don't want money being wasted or need to have it. – Kruug Jun 21 '13 at 17:22
@Kruug thanks for the advice. I used that SD card for about 5 months. I synced Dropbox to the SD card, and do you think that this made the problem? Thank you. – klados Jun 21 '13 at 17:33

Your SD card is probably in read-only mode, just try to mode the side "switch" to read/write mode. This will probably fix it, if not save your current files in your computer an run an sd formatter. If the problem still persists, run a "Check Disk" on the SD card. This will solve your problem, if you do all these and you can't still move files into the SD, that card is broken.

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I have the same problem with my Windows 8.1 laptop and just about every 64GB card I own.
The switch on the card is unlocked. When I write something onto the card, it appears as it should. When I safely remove it and check later, the files are gone. When I check it on a different laptop, they are gone. A Tech said he has heard (somewhere) that the larger memory cards are not being handled properly by Windows 8 and he recommended I go back to a 32 GB card. He tested several of his 16 GB and 32 GB cards (and two thumb drives) in my laptop. No problems. Thanks for listening.

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  1. Power off the phone.
  2. Remove the SD card and put it in a card reader and connect it to a PC.
  3. Run cmd to open a command window.
  4. Type chkdsk /f drive: (for example, chkdsk /f E:). You will probably see that corruption was found.
  5. Add files from your computer.
  6. Repeat chkdsk /f drive:.
  7. Safely eject the card and plug it back into your phone.
share|improve this answer

I know this thread is old, but here is an update about this issue, There were batch product line defective issue about SanDisk Ultra series microsd card, it will hold the data for the while(actually writen to cache) , but everytime you remove the card, it disappearrd. I own one SanDisk Ultra also and I returned it for RMA.

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