Hi Imen, Thanks for the reply. The error was quite scarce, not a frequent error, most of our devices can be reset manually and work can continue.In order to test properly, our code was changed to repeatedly initialize the SD card thousands of times u...

Thanks for the solution BTW ;) , kept me busy for quite a while, since it only failed sometimes in field, but with newer cards it seemed to be failing more often.

Can confirm, we have the exact same issue with newer SD card, and running the findSCR function @ 400KHz works. Tested findscr with a variety of SD cards at different clock speeds, with same results, some respond some of the time etc.Regards