Linux File Systems for Windows

Always disable “auto mounting” and make sure that you always UNMOUNT your card after you write to it or you will lose all the contents. Always unmount … always unmount.

The Steam Deck uses EXT4 formatting for its internal storage, microSD storage and any external storage that holds Steam games. Windows cannot access EXT4 drives – nor can it format a drive to that format.

In order for Deck Drive Manager to copy the Steam games from your PC to your Deck storage medium, you need a tool to allow read, write and formatting access to a drive.

For that, we need Linux File Systems for Windows (LFS) from Paragon Software.

This is not a free product but it comes with a trial period and after the trial, it will artificially slow down drive access until it is registered (the fee at the time of writing was a one-time perpetual license of $20USD). This is easily the best $20 I’ve spent on my Steam Deck since it arrived.

While this product is very good, it isn’t perfect – especially in use with the Steam Deck. It has a couple of interesting idiosyncrasies that can cause a new user some discomfort – and this page will help address those issues and make you a LFS pro in no time.

How Does It Work?

LFS quietly runs in the background waiting for you to insert a drive that is formatted in a Linux file system like EXT2/3/4 or BRTFS.

You can then mount the drive just like any other drive on your PC and the Steam Deck drive will be given a drive letter.

At that point, any file manager or tool (like DDM) can access the contents of that drive.

What Can It Do?

For EXT2/3/4 Drives: (like the default Steam Deck format):

  • Read
  • Write
  • Format (meaning you don’t have to trust the Steam Deck to format your microSD card)

For BRTFS Drives: (some people format drives in this format because Windows – with a driver – and Steam Deck can work with these volumes)

  • Read (so BRTFS drives cannot be used with DDM as it at least needs the ability to WRITE to the drive)

    * Note: Using the free Windows BRTFS driver in versions of Windows higher than 10 (e.g. Windows 11) appears to cause corruption, blue screens of death and other undesirable events)

Common Issues and Solutions

After using LFS to work with my drive, it appears to be write protected when using it on the deck. I get a DISK ERROR when installing Steam games, I cannot write to the root of the drive or folders created when using LFS.

There are some permissions quirks between LFS and the Deck. Fortunately, they are pretty easy to work around.

First, always mount the drive in LFS as User 1000 and Group 1000 while manually setting permissions to 777. This will make all subsequent folders created to be accessible by the Deck. This is commonly an issue when a new microSD card is prepped for the Deck and the steamapps folder isn’t already created by the Deck.

If the steamapps folder is already made under a different set of permissions, the command below will also clear the issue. Keep reading.

Unfortunately, writing to the root of a LFS formatted drive requires a bit of fixing while on the Deck itself.

sudo chown -R deck:deck /run/media/<volumename>

Run this command from konsole and replace the <volumename> with the name of your Deck’s SD card. This should restore the ability to write/install new games.

As of V0.6b, DDM can export the above command (customized for your drive) to a text file to the root of the drive which you can open, cut and paste and execute in konsole to change ownership on the drive to behave with the Deck.

The microSD card isn’t mounted the same when formatting outside the Deck and it is causing my installed stuff like EmuDeck to stop working.

This can happen in one of two ways; most likely it is because you gave the volume a name when you formatted it with LFS. When you do this, Deck will mount the card by that name instead of the normal mmcblk0p1 location.

Sometimes, even when you format the card without a volume name, the Deck will mount it in another location with a similar series of letters – but since your installed software is expecting the content at mmcblk0p1? It won’t run right.

Try removing the card and rebooting your Deck. Then insert the card and see if it shows up at the correct mount point.

Bottom line: Always format all your microSD cards the exact same way (and if you use a volume name, always use the same one), and you shouldn’t have issues.

Format MethodPath / Drive Name On Deck
Steam Deck Formatted/run/media/mmcblk0p1
LFS Formatted (no Volume Name)/run/media/mmcblk0p1 (but can show up as something else)
LFS Formatted (w/Volume Name)/run/media/<volume name>