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Windows Phone Permanently Modifies MicroSD Cards, Warns Samsung 426

dotancohen writes "Don't put your MicroSD cards into Windows Phones. According to Samsung, doing so is a 'permanent modification' to the card, and it can no longer be used in other devices."
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Windows Phone Permanently Modifies MicroSD Cards, Warns Samsung

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  • Probably fixable. (Score:1, Informative)

    by Anonymous Coward on Sunday November 14, 2010 @02:43PM (#34223886)

    I'd try SDFormatter to fix them.

  • by ehntoo ( 1692256 ) on Sunday November 14, 2010 @02:43PM (#34223890)
    The ghacks story that is linked to just cites engadget as a source... who don't mention *anything* about it "permanently modifying" the MicroSD cards, just that the manufacturers and microsoft are requiring that the cards are certified.
  •     I skimmed the articles, and they were short on information regarding exactly what was done.

        I don't know anyone with a Win7 phone, nor do I expect that any of my friends will get one, so I won't have a chance to test it. My suspicion is that they use yet another filesystem, which is unusable by other platforms. To the best of my knowledge, there's no way to permanently write to a card so it can only be used on a device. The only way to make a card unusable is to write to it too much, making it worthless to any device. I've only done that to a few. :) If there is a way, I'd love to know how. It would be nice to set up a card that can only be read on *MY* machine, so if someone snags it, they can't read the contents.


  • by Anonymous Coward on Sunday November 14, 2010 @02:45PM (#34223908)

    best guess is this socalled permant modification is changes to the filesystem nothing more, which for normal users would amount to the same, if their windows platform cant see the card anymore, inserting such a card would not be shown by windows except for people entering the computer management/ disk management and repartiton/format it again.

    Not quite - other reviewers have tried this, and even the partitioning tools get a "media not foud"-ish error. Nice one MS - bone everybody for your FAT32 "patents" for years, then ditch it entirely for a double-secret proprietary format. Remind anybody else of "Plays-for-(not)-Sure"?

  • Re:Pointless (Score:5, Informative)

    by Chaos Incarnate ( 772793 ) on Sunday November 14, 2010 @02:46PM (#34223918) Homepage
    It's not a "normal" consumer accessible slot; they're buried, and you have to disassemble the phone and void your warranty to get at it. As far as the consumer is concerned, it's not even there.
  • by QuietLagoon ( 813062 ) on Sunday November 14, 2010 @02:53PM (#34223972)
    From the engdget article:

    But what appears to have fried our card is the fact that any card inserted into a Windows Phone 7 device "will no longer be readable or writable on any other devices such as computers, cameras, printers, and so on" according to documentation on Samsung's site -- including, amazingly, the ability to format the card.

    Sounds like the card is being "permanently modified" (and not for the better) to me.

  • by Nukenin ( 646365 ) on Sunday November 14, 2010 @02:53PM (#34223978)

    From Microsoft's KB2450831 [] support article:

    Windows Phone 7 Secure Digital Card Limitations


    Some Windows Phone 7 devices include a Secure Digital (SD) card slot underneath the battery cover. If you buy a Windows Phone 7 device that includes an SD card slot, you should be aware of several important differences from other devices that use SD cards:

    • The SD card slot in your phone is intended to be used only by the Original Equipment Manufacturer (OEM) that built your phone and your Mobile Operator (MO). These partners can add an SD card to this slot to expand the amount of storage on your phone.
    • To help ensure a great user experience, Microsoft has performed exhaustive testing to determine which SD cards perform well with Windows Phone 7 devices. Microsoft has worked closely with OEMs and MOs to ensure that they only add these cards to Windows Phone 7 devices.
    • You should not remove the SD card in your phone or add a new one because your Windows Phone 7 device might not work properly. Existing data on the phone will be lost, and the SD card in your phone can't be used in other Windows Phones, PCs, or other devices.


  • by Graff ( 532189 ) on Sunday November 14, 2010 @02:56PM (#34224018)

    If this is even possible there is something really wrong with the SD card in question

    You have to dig further into the links in the article to find out what is really happening []. Apparently the Windows Phone 7 devices are stressing the SD cards in a manner which is not in-spec for a normal SD card. This means that a SD card which is perfectly fine by the normal spec might be ruined by the way the Windows Phone 7 OS uses the card [].

    This means that you will need a SD card which is certified under more stringent requirements in order to not be destroyed by the Windows Phone 7 OS.

    On top of that the OS also completely reformats the card so that it is a "permanent" part of the device. It probably sets up special space for swap space and other OS-specific data structures so that they can be accessed quickly and easily by the OS but this results in the card not having a normal disk layout that other devices can read using default software.

  • by Haedrian ( 1676506 ) on Sunday November 14, 2010 @02:57PM (#34224020)
    It would be nice to set up a card that can only be read on *MY* machine, so if someone snags it, they can't read the contents.</p><p>

    You could always try encryption - there are many programs which will encrypt any read/writes made to a particular drive
  • by eatvegetables ( 914186 ) on Sunday November 14, 2010 @03:16PM (#34224194)
    Was this really a surprise? Sure, no one probably saw this particular problem coming, but we all knew something really screwed up would be discovered soon after MS released its "Win7" mobile OS. The only question here is whether "MS certified" is a lame attempt to make excuses for the problem or if represents a new revenue stream creation strategy. Watch out, now MicoSD cards have to be "certified" to work in a MS product. Something tells me that the certification comes cheap. Thank God that we all still have MS to point to and laugh at!
  • by Anonymous Coward on Sunday November 14, 2010 @03:24PM (#34224264)

    DRM is not Security.
    DRM is Slavery.

  • Re:Probably ExFAT (Score:5, Informative)

    by Anonymous Coward on Sunday November 14, 2010 @03:31PM (#34224318)


    Anandtech ( say:

    The other interesting thing is that cards initialized on WP7 are locked to a specific device, and moreover, stop being recognized on the desktop - perhaps permanently. I took the card out of the Surround and spent considerable time trying to make it format, first on Windows, then OSX, and finally linux by trying to write zeros and random data to the disk using dd. This failed, as I only managed to get 'medium not present' errors every step of the way - in fdisk, gparted, every trick I know for really nuking storage.

    So, it actually does trash the card. There may be a way around that, but if there is so far some fairly smart people have failed to find it.

  • Re:Pointless (Score:3, Informative)

    by Spad ( 470073 ) <> on Sunday November 14, 2010 @03:39PM (#34224374) Homepage

    They are on Win7 phones - I think all the ones I've seen reviewed so far have placed the MicroSD card slot behind a "Warranty void if removed" sticker in one way or another.

  • by Dr. JJJ ( 325391 ) on Sunday November 14, 2010 @03:46PM (#34224432)

    I've been studying SD cards for the last few months and I've managed to dig up some heretofore "secret" leaked documents about SD Digital Rights Management mechanism and I think I know how such a permanent modification could be performed.

    One of the things that all SD cards support is the ability to designate a certain portion (which can include ALL) of the card's block storage as "secure". Once designated as secure, the blocks in question cannot be read, written to, or the area resized without performing an authentication step with the card. This authentication step is known as "AKE".

    I'm willing to bet that the phone is using this "secure" facility and marking the entire card, or some significant portion thereof, as a secure storage area.

  • WM6.5 has an option to encrypt the card, making it readable only on the device that performed the encryption, but I haven't used it, so I can't tell you how well does it work.

    What I do know is that you could always encrypt the whole card with TrueCrypt, making it readable only to YOU, provided you don't share the key.
  • by BradleyUffner ( 103496 ) on Sunday November 14, 2010 @04:00PM (#34224570) Homepage

    Furthermore is there any warning on the phone that it alters SD cards as such?
    This sounds like a major defect in both the phones and the SD cards.

    There is a yellow sticker completely covering the SD slot that says it will void your warranty if it is removed. I think that's' warning enough that it isn't a general purpose SD card slot. It also required an SD card that is certified as Windows Phone 7 complaint. Currently no such cards exist.

  • by Graff ( 532189 ) on Sunday November 14, 2010 @04:04PM (#34224606)

    So if we follow your link and find out what is "really happening," we find out that some blokes plugged a card into a phone and that it seemed to kill the card.

    Of course if you read the second link [] I posted you'd see that Microsoft itself spells it out a bit more clearly:

    When the operating system integrates the SD card with your phone:

    1. It reformats the SD card.
    2. It creates a single file system that spans the internal storage and the SD card.
    3. It locks the card to the phone with an automatically generated key.

    From this point on, the phone's operating system uses all of the available memory as a single storage space for storing applications and data. The phone will stop working properly if you remove the SD card, and the SD card cannot be read by another phone, device, or PC.

    It's not just one data point from some casual observer. The manufacturer of the operating system states quite clearly that this is the expected behavior.

  • by phantomfive ( 622387 ) on Sunday November 14, 2010 @04:16PM (#34224694) Journal

    It probably sets up special space for swap space and other OS-specific data structures so that they can be accessed quickly and easily by the OS but this results in the card not having a normal disk layout that other devices can read using default software.

    Specifically, it sets up a kind of RAID0, with the data being striped across the SD card and the internal flash. In theory this speeds up access to data in permanent storage, but I haven't really noticed a difference compared to Android phones. The downside is that if you remove it, both the internal and external SD card cannot be recovered, and all your data is lost (since the data is spread between both).

  • Re:Zap the card (Score:3, Informative)

    by segin ( 883667 ) <> on Sunday November 14, 2010 @04:41PM (#34224848) Homepage

    Secure Digital includes DRM. See this article [] for more information.

  • by bloodhawk ( 813939 ) on Sunday November 14, 2010 @04:44PM (#34224870)
    The SD card in question is not supposed to be a removable peice of the device. some phones even have it soldered in. Others have labels on it saying removing it voids your warranty. It may be an SD card but in this case it is the equivalent to prying a chip off the board and replacing it with your own and being pissed that it didn't work.
  • by bloodhawk ( 813939 ) on Sunday November 14, 2010 @04:47PM (#34224896)
    To Joe Blow the SD card in question is completely inaccessible, even soldered in on some models in others it is under the board itself and requires considerable effort to even find it let alone replace it. There is no way the average person will mistakenly replace the SD card in question.
  • by Anonymous Coward on Sunday November 14, 2010 @04:51PM (#34224934)

    there are few errors in the observations made by non-experts.

    as an expert in sd card, here is what is going on.

    1. card is locked as supported by the 2.0 specification.
    2. a locked card can be unlocked in two ways -
    2.1. temporarily unlocked the card with old password, and send clear password command with the old password to the card.
    2.2. force-erase the card.
    3. a locked card can't be unlocked via current desktop OS just because desktop OS can't send low-level command.

  • by Que_Ball ( 44131 ) on Sunday November 14, 2010 @04:58PM (#34225012)

    The SD Card can be locked to a specific device using a password.

    example: []

    An SD card can be locked using a password, or it can be set to permanent write protected mode.

    Also the manufacturer of an SD card may not include the secure features in their cards (which would probably mean it wouldn't work on these phones)

    From the linked article:
    Technologic Systems has developed a Linux application named "sdlock" which can be used to manipulate SD card hardware-enforced password locks and set the card's permanent write-protect feature. Using a password protected SD card is a great way to ensure software security and/or to make sure your TS-7000 SBC based product cannot be used in an unintended matter once deployed. This utility is only available for the TS-7300 and TS-7400 products, which are configured with the TS-SDBOOT firmware.
    Some of the possibilities include:
                    Password protecting SD Cards
                    Set the SBC to boot only locked SD Cards
                    Set the SD Card readable only on a specific SBC
                    Checksum verification of bootable SD Cards
                    Make an SD Card permanently write-protected
    How To Use It
    Usage and command line help for this command:
    $ sdlock –help
    Usage: sdlock [OPTION] ...
    Controls SD card lock and permanent write-protect features.
    General options:
    -p, --password=PASS Use PASS as password
    -c, --clear Remove password lock
    -s, --set Set password lock
    -u, --unlock Unlock temporarily
    -e, --erase Erase entire device (clears password)
    -w, --wprot Enable permanent write protect
    -h, --help This help

  • by BradleyUffner ( 103496 ) on Sunday November 14, 2010 @05:14PM (#34225164) Homepage

    Its not a warranty issue to remove a removable add in storage.

    Well that's the issue, it's NOT supposed to be removable storage. Even if it didn't "break" teh card it still wouldn't be general purpose removable storage. The phone reformats the card along with the internal storage to create a single Volume, kind of like a RAID mirror. Taking out the card would make you lose all your data, on both the card and the internal storage. The only reason it uses an SD card is because it's convenient to build, and it allows the different providers to use whatever size storage they want. In this phone, the SD card it not a user serviceable part.

  • by SuricouRaven ( 1897204 ) on Sunday November 14, 2010 @06:31PM (#34225788)
    Specifically it means the cards support the old CPRM scheme. When first invented it was planned to form part of a consistant, interlinked set of DRM technologies. Others in the suite included CPPM, CSS, DTCP, HDCP, Macrovision*, CGMS-D* and -A*, and a whole lot of others - all under the management of a consortium called the 4C entity. It was very elaborate, with a system of device revocation thrown in. The whole thing collapsed - a series of disasterous breaks of the constituent DRM technologies (Most significently CSS) caused a loss of faith in the idea to the extent that the supporting companies pulled out.

    A few of the technologies went on to be used on their own, without the unified framework - HDCP now forms the DRM component of HDMI, CSS remained in use on DVDs - while others fell into total disuse. CPRM is one of the latter. It's a dead technology, which continues to be present in SD cards like a vestigal organ because it's part of the SD specification. It's possible Windows Phone 7 is using a remnant of the old CPRM to encrypt SD cards - they arn't intended as removeable storage, but perminant upgrades to the phone.

    If this is the case, then it is possible to reset the cards (Doing so would render their existing contents unreadable, of course), but it would require software that I doubt anyone has ever had reason to write. No-one ever bothered cracking CPRM or even making tools to reset it, because no device ever used it. *Predated the unified framework initiative, but intigrated into it.
  • by Anonymous Coward on Sunday November 14, 2010 @07:17PM (#34226174)

    Sony didn't promote SD cards - in fact they have their own competing format called Memory Stick. (It too has DRM called "MagicGate" which AFAIK has never been used)

  • by shoehornjob ( 1632387 ) on Sunday November 14, 2010 @07:20PM (#34226200)

    Bah, that should be RAID stripe, not Raid Mirror

    Meh, considering how much data I've lost and restored from an external source on Windows 7 miroring is a good idea. And lets not even get into the time Windows 7 arbitrarily uninstalled my network connection. Bastards.

  • by Anonymous Coward on Sunday November 14, 2010 @07:41PM (#34226340)

    some heretofore "secret"

    It is called "Secure Digital" and one if it's main selling points when the cards were first released was DRM. But good work :-)

  • by vux984 ( 928602 ) on Sunday November 14, 2010 @08:28PM (#34226630)

    Nice examples, but there's no reason that audio won't work over DVI equally well as over HDMI.

    I don't claim to be an expert, but to my knowledge the DVI spec doesn't include audio.

    However, yes, its becoming common for PC video cards to provide it anyway. I'm not aware of anything else that can do it "natively".

    Normally you need something like this... []

    Which takes separate dvi+spdif and outputs hdmi.

  • by cookd ( 72933 ) <douglascook@ju[ ]com ['no.' in gap]> on Sunday November 14, 2010 @10:26PM (#34227304) Journal

    1. The "modification" mentioned is that Windows Phone uses the "LOCK" command of the SD card, which sets a password on the card. This is not commonly used, but it is part of the SD card standard. The S in "SD" stands for "Secure", and the "LOCK" command is one of the security features. It is possible to unlock the card via an UNLOCK command (requires the password) or via the ERASE command (does not require the password). Unfortunately, tools that support the LOCK, UNLOCK, and ERASE commands are essentially non-existent on Windows and (as far as I know) Linux.

    2. The "special" card required is really just "fast" (can sustain a reasonable number of reads/writes per second) and "reliable" (properly implements the SD card spec and doesn't glitch out too often). The SD card's "class" doesn't matter here, as the class essentially measures how quickly an SD card can carry out a single large read/write operation, while phone performance depends more on how quickly the card can carry out a large number of small read/write operations. Microsoft tested a bunch of SD cards from a bunch of different vendors and found exactly one that met the minimum reliability and performance requirements. This is now the "approved" SD card. It is a class 2 card, which means it isn't particularly great at saving big JPGs, but it had much better random I/O scores than anything else that was tested. Microsoft doesn't sell this card and as far as I know has no financial interest in the sale of the card. Any card that meets the reliability and speed requirements will work just fine in the phone -- the phone isn't programmed to look for anything special in the SD card.

    3. The confusion here comes from the fact that the SD slot is supported in a Windows Phone as a way for the retailer of the phone to easily upgrade the storage without involving a soldering iron, not as a way to share files between the phone and other systems. Selling a Windows Phone with an SD slot is like selling a computer with an unused SATA RAID port -- the user can add storage without going back to the manufacturer, but most users aren't expected to add or remove their computer's hard drive on a daily basis.

  • by fiddley ( 834032 ) <(partiedout) (at) (> on Monday November 15, 2010 @05:01AM (#34228904) Homepage
    The SD card market is chock full of dodgy cards, even from reputable manufacturers, in this case it seems Microsft is not actually pulling our chain: []

    Also, they've done a KB explaining what happens when you change cards: []
  • by FastNat ( 1940934 ) on Monday November 15, 2010 @03:07PM (#34234038)
    Actually the issue is that they used Cmd 42 (SD Lock/Unlock) card; this basically disables the card unless you have the password -- you cannot reformat the card w/o the password. Basically only a few commands work while the card is locked; and until you unlock it; your stuck. You can unlock it on ANY device so it isn't locked to the device so much as the password...

    See: [] for the full details.

    Now a good question is if the WM7 uses the same password for all roms; or if it uses a hash based on the model/serial number or if it generates a password that it stores somewhere...

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!