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.

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.

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

8bitkid i have thesame problem as you. Couldyou finally fix it? if so, how did yo do it?

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!

It works correctly with the SD cards (not SDHC) I've tried. I haven't tried SDHC cards.
What type of card are you using?

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!

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 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!