I got 4GB class 4 micro cards and they worked instantly. Roku's instructions for adding an SD card say nothing about max class or size, and they should. This was way more frustrating than it should have been.
These were the micro cards I got, and they came with an sd card reader (sd size, not usb).
https://www.amazon.com/gp/product/B08L8RC2Y2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
In case anyone is having he same issue, as I was, I think I can save you some trouble. I read all the ideas on this and other forums and tried all sorts of things, but nothing worked. Finally I determined that my SanDisk card will not work. Unfortunately, Roku is out of stock on theirs. Based on some other testimonials I bought this Kingston card:
https://www.amazon.com/gp/product/B000VX6XL6/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
(My Roku 3 will only format 2 GB but that card is 4 GB) It worked right away, without any of the tricks that other people advise, like formatting it in advance. I installed it with the unit on, but the HDMI cable removed. Once I plugged the HDMI back in I was prompted to format the card, which I did.
By the way, the card goes in with the contacts facing up, towards the HDMI slot. It won't go in the wrong way.
My last response posted my answer, so not sure why you are posting another response.
wow...weird fix but totally worked. My Roku 3 recognized the SD card on the 6th try
Bought a new card and it still doesn’t work
@Mrstaz3 can you post which card you have? I got this one and it worked:
https://www.amazon.com/gp/product/B08L8RC2Y2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
There does seem to be a size limit, so if your card has too much space, it may not read it. Try formatting it first, and know it will pop up a message like right away if it sees it. Also make sure your Roku has all its updates and a fresh reboot, before inserting it.
**bleep** @Roku -- they should just get rid of the memory nag. If they keep it, they should say there's a size limit, and the microsd card slot on the Roku 3 is upside down, and other gotchas . Maybe just point users to this embarrassing (for them) forum. After the time and money ($11 for the card) wasted on the not-right-sized card, it's really a MUCH MUCH MUCH better idea in retrospect to just get rid of unused apps and/or live with reloading some apps once in a while.
Now that I have the cards (right size) in the two Roku3's I have, I haven't had any issues, so I'm glad I got it working. I don't have an sd card in my roku ultra, and that one doesn't seem to have any size issue, even though it has the same app/channels.
They definitely need to update their online instructions to explain the limit on the size, which way to insert it, that you should insert it when the roku is on, updated, and after a fresh reboot, (to minimize any other issues) and then what you should see, when the roku does recognize it.
For something they bother users about relentlessly, they really offer **bleep** support for resolving it.
I’m having the same issue as many ithers about Roku 3 not recognizing the micro SD Card. Can someone who works for Roku address this issue??? I have reformatted the card three times and back to default. It’s a class 4 Sandisk 8GB card. I got the right card and I’m doing everything right and it still won’t recognize that there is an SD card inserted.
Thanks for the post.
Customers have reported that using a 4GB class 4 card worked with their device. Have you tried using a smaller size card to see if that resolves the issue you are experiencing?
Please keep us posted what you find out.
Thanks,
Danny