SD Card Slot is Read-Only

OK, so I have found a solution. For me anyway. The "lock" switch on SD cards can be in either locked or unlocked position. OR, you can actually slide it part way between. It appears as though the sensor on my MacBook Pro is faulty and if I slide the "lock" switch on the card half way between locked and unlocked then the card is read-write mode.

If the switch is in either the fully "locked" or fully "unlocked" position the card will show up as read-only!

I will probably go to Apple and get it fixed.

Okay, I found another solution that works at least on my 15" MBP.
Based on the other posts I figured that the problem must be the fickle built-in card reader (probably bad tolerances). So, depending on HOW I insert the SD card (ever so slightly angled) it will show up either read-only or read/write. I've tried it numerous times and it's 100% predictable on my machine:

When I push it in on the corner that is closer to the display, it will be read-only.
When I push it in on the corner that is closer to me, it will be read/write.

I'm having the same problem with my 2.66 GHz MacBook Pro. Tried both SanDisk Ultra II 16GB card and a SanDisk 512MB card. Both are read only.

My friend has the same exact model of MacBook Pro, both running Snow Leopard. I can plug both cards into his machine and they both work PERFECTLY and I can read and write to the cards.

If I plug the cards into my machine's slot they end up read only. If I use a USB card adapter then I can read & write!

Something is wrong with this MacBook Pro!

Same problem here! Does ANYONE out there have a solution?! The 'write protect' tab on the SD card doesn't make a difference for me.

Any help would be appreciated!

This is a great find as a solution.

As I was reading in other discussion thread, it appears that when the chip has been formatted by a camera, it becomes a little "unrully" when you attempt to change its content via a computer. Taking picture out is not problem, but adding pics onto the chip, is what causes the "read & write" to become "Read only" in the unlocked position.

So I don't think it's your Macbook pro is at fault, but simply the temperament of the chip having been formatted by a camera. I'm using a macbook, and 2 G5 and 10.4.11. No matter where I connect my card reader, i get read only....untill your marvelous suggestion of putting the switch half way in between. it's Genius! (We have to take matter into our own hands.... Technology cannot take over us! - LOL- joke) Maybe this glitch has been worked out in Snow leopard and is the reason why on your friends computer it's working fine.

if you formatted the chip via your computer, i read it would likely be more "compliant" but might not work properly in your digital camera.

In my case I am using the SD card in my son's digital picture frame, and we need to keep adding pictures!

Enjoy!

Michel

I don't have a solution for you, only an idea... I don't know what you are using these cards for (or had used them for), but maybe the are formatted in a way that can only be mounted as read-only, such as FAT32, NFS or some other non-HFS, non-FAT filesystem.
If it's a card that you will only use on your mac, check it out with disk utility and reformat if that suits your need.
Steve

I have the same problem.

I use an SDcard that can be flipped open to form a USB. When I use it as a USB, nothings wrong, I can read and write. But when I put the card in the SDcard slot, I can only read..

(this is the card I'm using (2GB version): http://www.amazon.com/Sandisk-SDSDPH-1024-901-Ultra-Retail-Package/dp/B0009HTB0Y )

So I'm pretty sure it's not something to do with the card itself, but rather the SDcard slot in the Macbook Pro..

Does anyone have a clue as to what might solve this?

Have you tried both settings of the 'write protect' switch on the side of the SD card? It's possible that some card readers don't honor that switch - but the Mac definitely does.

I just tried my Sandisk Ultra II (1GB) on my Macbook Pro 13" - it worked correctly, and properly handled the 'write protect' switch.

I have several cards and some have been formatted by a camera and some haven't. Either way it doesn't make a difference.

I have 2 MacBook pros sitting side by side and one has this issue and the other one doesn't. It appears that the sensor in the built in reader is just faulty on some machines.

here's an update

Just went to the Apple store today and spent some time with a Genius..after messing around a bit, we discovered tha tmy portable card reader is the culprit.

I have 2 SD card. 1- Sandisk, 2nd Lexar. The sandisk get Read Write with switch in the middle position, but not the Lexar. I only get Read only. We tried different cables etc..... and then a different Card reader... and suddenly the Lexar became Read/Write. Bingo! A mixture of palying around with the switch for the Sandisk, and a new card reader with the Lexar SD card.

I tried to connect the camera directly to the macbook wia it's cable... but icon does not appear.

et vpoila more info to play with!

Well my camera is PAnasonic..but I do not connect it directly to my laptop. But my son's camera isa Kodack, and when I plug the camera to laptop, the camera screen becomes black, and SD card icon DOES NOT appear to the desktop. I found that after I posted my last post.


Michel

I don't know whether a Kodak camera's card normally appears on the desktop or not, so what you see might be normal. When the camera is disconnected from the computer, can it use the card normally?

My experience with six different cameras ranging from a 3MP point-and-shoot to a 15MP DSLR has been that if I alter the contents of a memory card in any way while it's connected to a Mac, it probably won't be usable in the camera again until I've reformatted it in the camera. This is of no help to you with the problem of being unable to write to a card in your computer's SD card slot — that's clearly another problem. But it suggests to me that if you can overcome that problem, you should avoid using any card in your camera that you also use as a transfer medium between your computer and a digital frame. I recommend using two different cards for those different purposes: one that is only used to save pictures in the camera, and from which they are only copied to the computer *(without deleting them from the card while it's connected to the computer or adding any pictures to the card for transfer back to the camera),* and a different card that is used to move copies of the pictures from the computer to the digital frame(s) or any other device.

In my experience, it is unwise and will probably be unsuccessful to try to move any pictures from a Mac onto a camera card for viewing on the camera's LCD. Many people do this and some are successful, but it is no surprise at all to me when it fails to work as expected. I never allow my Mac to do anything to the contents of my camera cards except read and copy them. I never use my Macs to add or delete pictures or reformat a card: I only do those things using the camera's menu comands.

The suggestion to put the read-write switch in the middle totally works for me! It actually needs to sit just a tad forward of center. This works on about 5 cards I have at hand here. I think this must be poor tolerances in the built-in reader. I'm shocked, puzzled, amazed, but also glad to have a solution, however kludgy.

I wonder if there is a sensor in the reader that needs cleaning?

Message was edited by: LawsonStone

you're brilliant, thanks very much, that's exactly what it was!