When following the instructions for creating an SD card with leJOS, the brick freezes when it comes to the screen “Installing rootfs.” I'm using a new 32 GB SanDisk SD card. I've confirmed that I'm using the appropriate version of the Java runtime, and there are no error messages at all.

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I was able to fix the problem by creating a smaller partition on the SD card. (The idea came from this forum post; it was not necessary for me to buy a different SD card, despite what many people say there.) Using Windows 10, I was able to create a 4 GB partition with the “Computer Management” utility. After that, I used the ev3sdcard.bat utility again, and the installation completed successfully.

I do not know whether some intermediate value between 4 GB and 32 GB would also work. The forum posts I read suggest that 4 GB will be plenty of space.

  • Working on a Son's STEM Science Fair project, and your post here SAVED our bacon. We used a lexar 32 GB SDHC card. Some places say that SDHC isn't recommended, but it worked beautifully once we created the smaller FAT 32 partition of 4 GB using the "Disk Managment" partitioning tool. For anybody else who knows absolutely nothing about this stuff, don't let the mention of the ev3sdcard.bat utitlity (file) throw you off. That file is simply the little program that pops up in the top lefthand corner of your screen. The little program where you enter the JRE gz file and then click "create." THANK
    – Schmekis
    Jan 27, 2022 at 12:50

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