topic Re: Canon r6 mark II card slot problem "Card cannot be accessed" in EOS DSLR & Mirrorless Cameras

EOS R6 Mark II card slot problem "Card cannot be accessed"

Princejvstin — Tue, 15 Oct 2024 12:06:38 GMT

I really can't figure this one out, so maybe someone has some ideas.

About a year and change ago, I went from a Canon 5D Mark IV to a canon R6 mark II. Things went fine at first, but then I recently noticed I am having a bunch of SD card problems. I was getting the "card cannot be accessed" error

But its' frustratingly weird how the error happens:

It only happens in slot 1.

It only happens on cards larger than 64 GB. My 64 GB cards work just fine. I have a couple of different kinds of 128 GB cards in terms of manufacturers and they all act the same way. Any card larger than 64GB doesn't work in slot 1.

So if I take a 128 GB card and put it in slot 1, it gives me the error. I put that same card in slot 2, and it seems to work fine.

If I put one of my 64GB cards into slot 1 it seems to work fine.

I've tried formatting the cards, regular and low level format, to no avail. I've tried formatting the cards on a computer. No luck there.

And it is just slot 1. Slot 2, the 128GB cards work normal. Slot 1, "card cannot be accessed". But 64 GB cards work in slot 1, no issues. (and of course Slot 2, the 64GB cards work normal)

I even toggled the write protection switch on the cards back and forth. No dice.

It's as if my R6 Mark II can't "handle" a 128GB card in Slot 1. But Slot 1 can handle 64 GB cards. And the 128 GB card works in Slot 2.

I downloaded the latest firmware in hopes that would help. No dice.

Ideas?

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Stephen — Sun, 30 Jun 2024 14:53:08 GMT

Hey there!

I'm not a tech, but I want to help ensure you get the best answer to your question!

You mentioned upgrading your gear. Are you having problems with only older cards, or are brand-new, high-quality, high-speed cards also giving you errors?
Are your cards full-sized, or do you use micro-SD cards inside adapters? If you're using adapters, are you using the adapter that came with your card? (I've found that some older adapters were made for the older speeds and can't handle the high-capacity)
So that we're all on the same page, would it be possible for you to post images of the cards you're using? 🙏🏼

If you can think of anything else that might be useful, please share, so the Community can help!

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Princejvstin — Sun, 30 Jun 2024 15:20:51 GMT

Hi Stephen.

These are full sized SD cards. There are both type I and type II SDXC cards which are in the 128 GB set that aren't working. A picture of a 64 GB card that works without issue and the 128 GB problem children are here:

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

jrhoffman75 — Sun, 30 Jun 2024 17:01:37 GMT

"I've tried formatting the cards, regular and low level format, to no avail. I've tried formatting the cards on a computer. No luck there."

1. so formatting cards in Slot 2 works properly, but then putting the cards in Slot 1 they generate the error?

2. by "no avail" you mean that you can format the cards in your computer but Slot 1 generates the error?

You have Type I and Type II cards. Both slots are Type II compatible, so that doesn't seem to be the issue.

Can you shine a light into Slot 1 and see if anything looks amiss? Do you have a Rocket Blower that you can use to blow out the slot?

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

megnani — Sun, 30 Jun 2024 18:12:20 GMT

The following content was generated by AI. It may contain errors or inaccuracies, and should not be relied upon as a substitute for professional support.

If you're encountering a "Card cannot be accessed" issue with your Canon R6 Mark II camera, here are some steps you can try to resolve the problem:

1. **Check the Card**: Ensure that the SD card or CFexpress card is inserted correctly into the camera slot. Sometimes, improper insertion can cause connection issues.

2. **Restart the Camera**: Turn off your camera and then turn it back on to see if the issue persists. Sometimes, a simple restart can resolve minor glitches.

3. **Format the Card**: If the card is not recognized, try formatting it using the camera's format option. Formatting can sometimes resolve file system errors.

4. **Try a Different Card**: Test the camera with a different SD card or CFexpress card to determine if the issue lies with the card itself.

5. **Update Firmware**: Ensure that your camera's firmware is up to date. Manufacturers often release updates to fix bugs and improve compatibility.

6. **Clean the Card and Slot**: Use a clean, dry cloth to wipe the metal contacts on both the card and the camera's card slot. Dust or debris on these contacts can sometimes cause connectivity issues.

7. **Check for Physical Damage**: Inspect the card and the camera's card slot for any physical damage or debris that might be obstructing proper contact.

8. **Reset Camera Settings**: As a last resort, you can try resetting the camera settings to their factory defaults. This can sometimes resolve software-related issues.

If none of these steps resolve the problem, it may indicate a more serious hardware issue with either the camera or the card itself. In such cases, contacting Canon support or visiting a certified service center for further assistance would be advisable.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Princejvstin — Sun, 30 Jun 2024 18:07:15 GMT

1. The cards work in Slot 2 but not Slot 1

2. I've restarted the camera dozens of times.

3. I've tried formatting the 128GB cards multiple times
4. As I said in my post, 64 GB cards work fine in Slot 1. 128 GB cards do not.
5. As I said in my post, I did that. No change.
6. I've tried this, with a rocket blower. Not sure why it would mean that "small cards will work" but larger ones won't in the same card.
7. Again, if there was physical damage. why do the small cards work and the large cards don't?
8. I have not yet contemplated this because I don't want to lose all of my custom settings. But this is a good idea.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Princejvstin — Sun, 30 Jun 2024 18:08:46 GMT

1. Correct. And the cards work in slot 2 just fine (just verified today in fact). But when I put the 128 GB card in slot 1, the camera can't handle it.
2. Yes, No matter where I format the card, slot 1 can't handle the 128 GB cards, only 64 GB
3. Tried the blower, nothing came out. I don't see anything wrong when I look in with a light.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Stephen — Sun, 30 Jun 2024 18:09:18 GMT

We encourage you to acknowledge when you've used AI as your source of assistance, as it may not be completely accurate.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

jrhoffman75 — Sun, 30 Jun 2024 18:12:34 GMT

Very strange. I don’t recall anything like this previously posted on the forum.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Stephen — Sun, 30 Jun 2024 18:22:21 GMT

John,

Are you referring to my comment about AI? It's because AI is becoming increasingly prevalent. The post I modified was copied/pasted from ChatGPT. While I find much value in utilizing AI as a starting point to help find information, it is imperfect. We need experts like you to help with real-world scenarios. AI can't do that, so it's important to alert other members of the Community that #1, you aren't speaking from your learned experiences, and #2, the information you're presenting isn't your original content.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

jrhoffman75 — Sun, 30 Jun 2024 18:54:30 GMT

Hi Stephen. No, I was replying to princejvstin ( the OP). Never saw his problem before.
I have noticed a number of posts that appear to be AI. As you say, they tend to be generic and lack specific details of the problem.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Stephen — Sun, 30 Jun 2024 20:06:40 GMT

When you suspect something is AI, please report it so we can moderate accordingly. 😊

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Princejvstin — Sat, 06 Jul 2024 12:10:02 GMT

Update:

I bought a new 128 GB card.

This card worked and works just fine in the slot, none of the card cannot be accessed errors. Took some photos with it (4th of July fireworks). Yes, I also had a 64 GB card in slot 2 just in case this one was going to choke on me.

So...is this a case of a whole set of cards that got semi corrupted? I...don't know. I am going to keep watching and keeping watch on this new card to see if it "Corrupts" as well

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

shadowsports — Sat, 06 Jul 2024 13:58:56 GMT

Greetings ,

I believe I posted about something similar recently. R62 and card requirements for recording high quality video. Recording media can be very important for reliability and performance.

Although the R62 is backwards compatible with UHS-I, I would recommend UHS-II v60 and v90 cards. It's more important for video , but this way you don't have to watch what you're putting into which slot. It might be wise to retire your aging stable of cards. You can watch for sales at B&H, Adorama or your local Best Buy. 64 and 128 GB. UHS-II cards are more affordable than you might think. Hopefully this will put an end to your strange card/slot behavior.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

melissatoms — Tue, 15 Oct 2024 00:59:45 GMT

I started having this same exact issue this week with my R6 mark I. Did you ever come to a conclusion or a solution for 128 GB cards? Did all new cards work?

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

Princejvstin — Tue, 15 Oct 2024 09:35:28 GMT

Unfortunately, no, the slot now seems it doesn't work period

Re: EOS R6 Mark II card slot problem "Card cannot be accessed"

shadowsports — Tue, 15 Oct 2024 13:16:51 GMT

Greetings ,

It's time for the camera to visit Canon.

Re: Canon r6 mark II card slot problem "Card cannot be accessed"

melissatoms — Tue, 15 Oct 2024 15:09:51 GMT

Does the second slot work well enough for it to function? I have a back to back sessions over the next month and don't really have time to send it off to Canon yet. Right now it's working ok with a handful of cards, but worried it will give out on me in the middle of something important.

Re: EOS R6 Mark II card slot problem "Card cannot be accessed"

emloe — Thu, 27 Feb 2025 22:02:21 GMT

hi there! I recently came across this same issue a couple of times. Im wondering if youve found a solution since then? Thank you!!

Re: EOS R6 Mark II card slot problem "Card cannot be accessed"

ToniT — Fri, 11 Apr 2025 09:37:47 GMT

I have had the same issue with my R6 M2 in the same way with slot 1. To the point that when I first received the camera it wouldn't recognize anything in slot 1 (while slot 2 was empty), I bought a set of new cards and it only worked when i set it into slot 2.

Now I have 3 brand new cards:

Lexar Professional 64GB V60, SDXC II (1667x speed)
2x Lexar Professional 128GB, SDXC II (1800x speed)

I still have issues with slot 1.

When I set both 128GB cards in, it takes long time to start the camera up and the card reading/writing indicator led is lighting up at the same time. When it is done it allows me to open the menu or take pictures.

It works fine with only 1 card in slot 2.

64GB card works fine. Until I mix it with 128GB card and more specifically set the 128GB card into slot 1.

Sometimes I get card access errors. Sometimes it just takes a long time to fire it up. But it is always related to card slot 1.