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Main Forums => The Roundtable => Topic started by: Ben on October 08, 2016, 11:45:28 AM

Title: SD Card Write Protect Error
Post by: Ben on October 08, 2016, 11:45:28 AM
Anyone ever have this or know of a fix (besides, I suspect, getting a new card)?

I have an SD card that has started occasionally popping up as "this disk is write protected" when I want to modify or save something on it. It's done it four times now over a few months, with the computer generally turned on at the beginning of the day and off at  night. It lives in my main laptop and is only removed when I need to stick another SD card in the slot.

So far, if I reboot after getting the error, the card works normally again. I'm wondering if maybe the write protect switch is physically malfunctioning (which would mean "new card") or if this is some other kind of error.

All the obvious stuff has been checked - switch in proper position, files are not soft write protected, etc (I've copied the files to the desktop and they write fine there). Never had this happen on an SD card before, and haven't found much on the Googles.

Oh, ETA - the files are all in a large TrueCrypt file on this drive (the drive is not encrypted, I just have a Truecrypt file on it). Not sure if that has anything to do with it, given that I can write to them when they are moved elsewhere.
Title: Re: SD Card Write Protect Error
Post by: lee n. field on October 08, 2016, 03:32:17 PM
NEW cards are cheap, and cheap insurance.  My guess is the internal circuitry is getting flakey.
Title: Re: SD Card Write Protect Error
Post by: Ben on October 08, 2016, 03:43:48 PM
NEW cards are cheap, and cheap insurance.  My guess is the internal circuitry is getting flakey.

That's where I was leaning, since I wanted to move to a 256gb anyway. Just wondered if I was missing some easy fix. I keep important stuff on the drive (backed up of course) so don't want to take chances or horse around.
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 08, 2016, 06:42:46 PM
I had one do this the other day and it was because the switch on the card was loose and on insertion shifted to Locked and on withdrawal shifted to write. A drop of super glue solved the issue.
Title: Re: SD Card Write Protect Error
Post by: Ben on October 08, 2016, 06:46:57 PM
I had one do this the other day and it was because the switch on the card was loose and on insertion shifted to Locked and on withdrawal shifted to write. A drop of super glue solved the issue.

That was one of my first thoughts, except that if I leave the card in the slot and simply reboot the computer, the card will work normally again. Which I guess could also open things up to the internal card reader itself, though other cards don't seem to have the issue.
Title: Re: SD Card Write Protect Error
Post by: 230RN on October 08, 2016, 07:25:01 PM
Dirty/worn contacts?
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 08, 2016, 07:58:47 PM
That was one of my first thoughts, except that if I leave the card in the slot and simply reboot the computer, the card will work normally again. Which I guess could also open things up to the internal card reader itself, though other cards don't seem to have the issue.

Gently Clean the contacts on the SD card with a clean eraser.
Title: Re: SD Card Write Protect Error
Post by: 230RN on October 08, 2016, 10:43:02 PM
I got in the habit with high impedance devices to plug them in, unplug them, and plug them in again.  That's carried on to modern times with SDD cards, etc.

Yeah, yeah, wear and tear.

But yeah, yeah, good contact.

 :old:
Title: Re: SD Card Write Protect Error
Post by: Hawkmoon on October 09, 2016, 11:07:47 AM
I didn't even know SD cards had write-protect switches.

It's not even noon and my day is complete -- I learned something.
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 09, 2016, 03:04:03 PM
I didn't even know SD cards had write-protect switches.

Not really a switch as much as a slide that blocks a slot in the card to let the device know write/don't write.

(https://armedpolitesociety.com/proxy.php?request=http%3A%2F%2Fi.fixya.net%2Fuploads%2Fimages%2Fbea21a9.jpg&hash=2cf1766bd943fb5066254861b5871a7571409ad6)
Title: Re: SD Card Write Protect Error
Post by: Hawkmoon on October 10, 2016, 12:27:15 AM
Not really a switch as much as a slide that blocks a slot in the card to let the device know write/don't write.


Yes, like the plastic sliders on the old 3-1/2" (not so) floppies.
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 10, 2016, 01:24:35 AM
Yes, like the plastic sliders on the old 3-1/2" (not so) floppies.

LOL! I started typing that EXACT SAME SENTENCE!
Title: Re: SD Card Write Protect Error
Post by: Hawkmoon on October 10, 2016, 08:31:57 AM
I still have several boxes of those old 3-1/2" floppies, some new but most that hold "stuff." A few of them have "stuff" I may some day find useful, like collections of TrueType fonts, so while back I bought an external USB floppy drive so I'll be able to access them.
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 11, 2016, 01:02:05 PM
You have a Floppy drive?  :O

(https://armedpolitesociety.com/proxy.php?request=http%3A%2F%2Fherohog.com%2Fimages%2Fcomputers%2Fthen-now.png&hash=6c1db1eee759f380f696357846d50ddbfdc5b8fd)
Title: Re: SD Card Write Protect Error
Post by: KD5NRH on October 11, 2016, 01:29:14 PM
Dirty/worn contacts?

Problem is, there's no write protect switch on an SD card; it's just a slider not connected to anything.  The "write protection" is a function of the reader detecting whether the slider is physically in the "lock" position - pretty much like the notch on a floppy disc.  If it's being detected wrong, and the slider itself isn't broken, then the problem is in the reader.
Title: Re: SD Card Write Protect Error
Post by: HeroHog on October 11, 2016, 01:34:59 PM
I have ripped that dang slider out of one before when it ticked me off and I didn't have any SuperGlue handy...
Title: Re: SD Card Write Protect Error
Post by: RocketMan on October 11, 2016, 02:48:42 PM
Try applying a little canned air to the SD card reader slot on the PC.  Might have some gunk in there keeping it from reliably reading the state of the slider on the card.
Title: Re: SD Card Write Protect Error
Post by: KD5NRH on October 11, 2016, 03:18:03 PM
I still have several boxes of those old 3-1/2" floppies, some new but most that hold "stuff." A few of them have "stuff" I may some day find useful, like collections of TrueType fonts, so while back I bought an external USB floppy drive so I'll be able to access them.

Why not transfer them to paper tape so there's no risk of magnetic degradation?