Formatting an SD card/Windows

This is an add-on section for formatting an SD card to FAT32.

This page is for Windows users only. If you are not on Windows, check out the Linux or Mac pages.

What You Need

• For all SD cards: the latest version of SD Formatter
• For SD cards 64GB or larger: The latest version of guiformat

Instructions

1. Insert your SD card into your computer
2. If the SD card has any files and folders on it, copy everything to a folder on your computer
3. Run SD Card Formatter Setup (the .exe file) in the downloaded .zip file with Administrator privileges, then install the program
4. Run SD Card Formatter from the Start Menu
5. Select your SD card’s drive letter for "Select card"

   Make sure you choose the correct drive letter, otherwise you might accidentally erase the wrong drive!

6. Ensure that "Quick Format" is selected
7. Click "Format"
8. Click "OK"
9. Wait for the format to finish
10. Click "OK"
11. Close SD Card Formatter
12. Run guiformat.exe
13. Select your SD card’s drive letter for "Drive"

    Make sure you choose the correct drive letter, otherwise you might accidentally erase the wrong drive!

14. Select a size for "Allocation unit size"
    • If the SD card is 64GB, choose 32768
    • If the SD card is larger than 64GB, choose 65536
15. Ensure that "Quick Format" is selected
16. Click "Start"
17. Click "OK"
18. Wait for the format to finish
19. Click "Close"
20. If the SD card had any files and folders on it before the format, copy everything back from your computer

Common errors with guiformat

Failed to open device: GetLastError()=32

Close everything that may be using the SD card, such as any File Explorer windows.

GetLastError()=1117

Your SD card write-protection switch may be enabled. The lock must be flipped upwards to allow writing to the SD card (including formatting).

1. Insert your SD card into your computer
2. If the SD card has any files and folders on it, copy everything to a folder on your computer
3. Run SD Card Formatter Setup (the .exe file) in the downloaded .zip file with Administrator privileges, then install the program
4. Run SD Card Formatter from the Start Menu
5. Select your SD card’s drive letter for "Select card"

   Make sure you choose the correct drive letter, otherwise you might accidentally erase the wrong drive!

6. Ensure that "Quick Format" is selected
7. Click "Format"
8. Click "OK"
9. Wait for the format to finish
10. Click "OK"
11. Close SD Card Formatter
12. If the SD card had any files and folders on it before the format, copy everything back from your computer