Amazon.com - Kingston 8 GB microSDHC Class 4 Flash Memory Card SDC4/8GB
I ordered this card January 9, 2019. shipped and sold by Amazon. I have successfully used this card directly out of the package with the MP Mini Delta and MP Select Mini V2 for printing with no formatting required. I have not yet tested if it will work for updating the motion controller firmware.
Amazon.com - Kingston 2 GB microSD Flash Memory Card SDC/2GBSP (Single Pack)
This card seems to be either out of stock or overpriced more than it used to be. I guess I need to identify another known working card that is readily available.
I ordered this card December 14, 2017 from Amazon seller “i77e” to test after a number of people said they have used it without any issues.
I have successfully used this card directly out of the package with the MP Select Mini V2 and the MP Mini Delta for printing and also updating the Motion Controller firmware with no formatting required.
Try any card up to 32GB (yes some 32GB cards will work with the MP Select Mini V2 and the MP Mini Delta). FAT16 and FAT32 both work. Also exFAT works for some. The printer is picky about which cards it will read so if you have multiple microSD cards try them all.
You may also want to try formatting the larger cards such as 16GB and 32GB as FAT32 with different allocation unit/block sizes.
You can try the same with the lower capacity cards also but using smaller allocation unit/ block sizes. Also try FAT(16) with different allocation unit/ block sizes.
Follow the link below for more information.
Printer Stops or Never Starts Printing