Reply To: Mayfly v1.1 technical questions forum thread

As long as the cards are formatted for FAT32 and you can read/write to them with other Mayfly boards or Windows devices, then it’s possible the on-board memory card socket on that Mayfly is broken.  Is this a brand new board that you’re using a card in for the first time?  If you’ve got an EnviroDIY vertical microSD adapter you could try putting that on the Mayfly to see if a card will work in there, but sometimes we’ve found that the defect in the on-board socket causes the vertical adapter to also not work properly (because they both essentially share the same pins).  You can email me at mayfly@envirodiy.org and we can arrange the warranty support.