My Nintendo Switch microSD card filled up and I needed to move to a larger card. This would all be so much easier in Windows (see Nintendo’s official guidance). But I have Macs.

This method worked for me when moving data from a 128 GB microSD card to a 256 GB microSD card on Nintendo Switch Firmware 10.2 0.

Get the Old microSD Card Out of your Switch

Power off your Nintendo Switch. Not sleep, power it off.

Remove the microSD card. (The microSD card is located under the kickstand on the standard Nintendo Switch.)

Copy the contents of your old microSD card onto your Mac

Insert the microSD card into your Mac using whatever means works for you.

Launch the Terminal App and enter the following commands. A description of what the commands do follows.

mkdir ~/Desktop/MyOldSwitchMicroSDCard
cp -r /Volumes/Untitled/Nintendo ~/Desktop/MyOldSwitchMicroSDCard

The mkdir command is Make Directory, and it will create a directory on your desktop called MyOldSwitchMicroSDCard. You can change this directory name to whatever you want.

The cp -r command is Copy Recursively. This will copy everything from the Nintendo directory and its subdirectories on the old SD card, which by default mounts as /Volumes/Untitled/, to the MyOldSwitchMicroSDCard directory on your desktop.

Depending on the amount of data to be transferred and the speed of your gear this cp command may take hours to complete. Sit tight.

Setup the New microSD Card
You can perform this step while copying the old microSD card to your Mac.

Here’s how to format a microSD card with your Switch.
Ensure your Switch is powered off.
Insert the microSD card into your Switch.
Power on your Switch.
Select “Settings” form the home screen.
Select “System” from the settings menu.
Select Formatting Options.
Select Format microSD Card. Be careful to chose the right option here!
Continue.

This will wipe the microSD card and make it ready for use in the Nintendo Switch.

Now that your new microSD card is ready, it’s time to copy the content from your old microSD card on to it.

Copy the contents of your old microSD card from the Desktop onto your New microSD Card

Launch the Terminal App and enter the following commands to copy the content from your Desktop back to the microSD card.

cp -r ~/Desktop/MyOldSwitchMicroSDCard/Nintendo/* /Volumes/Untitled/Nintendo

Eject the card.

Put it in the new switch. Cross your fingers.

Press power.

After going through these steps, I noticed that all my games and save data seemed to be in tact. However, I was missing a bunch of photos and videos from the Album. No!!!! Not my Monster Hunter Ultimate kill screens and beautiful Zelda Breath of the Wild selfies!

To get the Album back, I tried running the the following commands from the reddit post in the Terminal App.

    sudo chflags -R arch /Volumes/Untitled/
    sudo chflags -R noarch /Volumes/Untitled/Nintendo/
    sudo mdutil -i off /Volumes/Untitled/
    sudo mdutil -E /Volumes/Untitled/
    dot_clean -m /Volumes/Untitled/

Not all of the commands executed successfully.

The first command failed with “.Spotlight-V100: Operation not permitted”.

The second command ran cleanly with no feedback.

The third command ran and returned with feedback finally saying “Indexing disabled.”

The fourth command also returned “Indexing disabled.” The final command failed saying, “Failed trying to change dir to .Spotlight-V100 Bad Pathname: Operation not permitted.

After running these commands, I could see everything I remember from my Album, however, now none of my non-cartridge games would launch. I would get an error message telling me to return Home and to try launching again.

Reading around I learned that one of the issues with Mac and Nintendo is that the Nintendo Switch does not play nicely with hidden directories and files that MacOS tends to put in its file structures. The hidden directories and files always have a dot at the beginning of the name. Like “.Spotlight-V100”.

Browsing the microSD card with Finder, and then hitting the Command+Shift+. keys together shows any hidden folders or files. Sure enough, I could now see the .Spotlight-V100 folder that was mentioned in the error messages above. I deleted that and emptied the recycle bin.

I reinserted the memory card into the Nintendo Switch, and now everything finally seems to be working!

Good luck! If you can avoid it, just do this on a Windows machine. I have also heard that if you don’t care about your Album contents, it may just be easier to swap memory cards and download everything again from the Nintendo eShop.

Whatever you decide to do, I hope it goes smoothly and that it doesn’t cost you much game time!

These tutorials were helpful!
FlynsArmy.com – https://www.flynsarmy.com/2019/07/how-to-transfer-data-between-nintendo-switch-microsd-cards-with-os-x/

Reddit.com How to transfer SD card data using MacOSX.

Reddit.com mentions using Command+Shift+. to show hidden files in Finder.

MacWorld on what those hidden folders are all about.