[AT&T Samsung Galaxy S 4 General] Lethalia:
Fake 64gb Cards

Just a thought... I didn't read through an entire 17 pages of replies, so please forgive me if it's already been mentioned.

I have found problems with a lot of 64gb cards being fake. They are bought on eBay and Amazon and listed as 64gb Class 10 SDHC cards. They are COUNTERFEIT. It doesn't matter whether the card is generic, or supposedly a "brand name." There are obvious or not-so-obvious problems on the packaging, no matter how close to legitimate looking packaging these jerks can get. Some of them do an outstanding job. It also doesn't matter if the sellers are caught, they just pop up with new accounts, pawning off their fake cards because eBay/Amazon won't or can't monitor users creating new accounts under a new name.

According to the SD Association (h t t p s: / / w w w.sdcard.org/developers/overview/capacity/), an SD card must be SDXC in order to hold over 32gb. SDHC cannot hold 64gb. Sorry, I couldn't post the actual link because I'm new. My conclusion is that if you have a "64gb SDHC" card, you are probably getting corruption and file deletion, or "damaged card" errors because the configuration file shows it has a 64gb capacity but the card is actually fake and most likely an 8gb or 4gb capacity card. You should just automatically assume that any card listed as "64gb SDHC Class 10" is fake. Even when it's printed on the card itself.

I had this problem personally and took me almost a month of tireless research and beating my head into my desk to figure it all out. I bought new "64gb Class 10 SDHC" cards, transferred just under 8gb of data from my old 8gb card that I was replacing and didn't have a problem at all for over a week. When I finally had time to start moving "new" data to it, all of a sudden my files were corrupted or just magically disappeared, deleting themselves "randomly." (It was actually randomly removing files to bring the total data on the cards under 8gb.) I reformatted and moved files one by one countless times and had no problems (as long as it wasn't going over 8gb total data on the card). I finally figured it out that any time I pushed the card over 8gb total (even though the card showed 64gb available space) my card was toast and my files were gone. Any time the card still had under 8gb (even if it was only 1kb under 8gb) everything worked fine. If it went even 1kb OVER 8gb, my problems started over. Note that I bought two different cards, two different brand names, from two different sellers, but both were listed as "64gb SDHC Class 10" and both were fake.

I even had someone tell me that the Galaxy S4 just couldn't handle or read a 64gb card, but I finally broke down and bought a retail 64gb SDXC card, and it works perfectly. The Galaxy S4 is not the problem, and it can handle a 64gb card just fine, as long as it's real. The fake SDHC cards are the problem - saying they have a 64gb capacity, but they really do NOT.

One of my cards was "generic" and the other a "genuine" Samsung. Both cards were listed as "64gb Class 10 SDHC" (again, not possible, and fake). Some problems I found on the packaging for the Samsung card: The packaging never mentioned anything about 64gb. The front of the package showed "Class 10" but right below that, it showed "7MB/s MAXIMUM" transfer rate. A real Class 10 card has a MINIMUM transfer rate of 10MB. The back of the packaging had a graphic table, listing file limits for 2gb, 4gb, 8gb, 16gb and 32gb cards, but nothing about 64gb cards, which is supposedly what I bought, and was supposed to be in the package.

Someone mentioned they couldn't move files over 1gb, but do some testing and see if that 1gb of data is pushing your data over a certain size limit on the card, and not that the size of the file itself is the problem.

After countless hours of research on my own problem, I also found an application (for the PC, not the phone) that will test the SD card and tell you exactly how much space is available on the card, proving it is a fake. You will need to use a USB card reader so you can get a drive letter for the SD card in Windows. I also recommend you format the card before testing. Just back up your data if you actually have anything on the card. If you got a flimsy plastic reader with the fake card, it probably doesn't work either, mine didn't. I bought one for $6 from BestBuy. The H2testw download page is in German, but Google will translate it. It's just a small .exe file that does not need to be installed. Just search Google for: "H2testw - Download - heise online." Sorry, once again, can't post a link because I'm new. The application itself is also in German, but there's a button in the interface that will let you switch it to English.

Here's the results I got from my test, showing that my generic "64gb SDHC Class 10 card" was actually only an 8gb card, probably with bad sectors so it only had 7gb total space available anyway. It says it's "likely to be defective" but that really means it's just not a 64gb card. The read/write speeds it found also prove it's not a Class 10 card.

Warning: Only 63995 of 63996 MByte tested.

The media is likely to be defective.

7.1 GByte OK (14969911 sectors)

55.3 GByte DATA LOST (116091849 sectors)

Details:0 KByte overwritten (0 sectors)

0 KByte slightly changed (< 8 bit/sector, 0 sectors)

55.3 GByte corrupted (116091849 sectors)

0 KByte aliased memory (0 sectors)

First error at offset: 0x00000001c8d86e00

Expected: 0x00000001c8d86e00

Found: 0xe378dd2d1bcc8688

H2testw version 1.3

Writing speed: 7.78 MByte/s

Reading speed: 15.5 MByte/s

H2testw v1.4​

Hope this info helps someone.