I had the same problem with f_mount(). I use the same solution as described by JBond.1https://community.st.com/t5/stm32cubemx-mcus/sdcard-does-not-work-with-4bits-wide-bus/td-p/602607It works fine! You don't need to do the steps described by TKana.1I...

Thank you both for your answers! That would be a very good option.