Sony Xperia Z corrupted photos in LOST.DIR folder inside microSD
well the 4.1.2 was in the fat32 format however the 4.2.2 wants a "exfat" but becarefull since this format is very weird because in not always working due to the fact that the master table very messy therefore it might asking for the deframenting often. so it can lock it self 0x.... 
So re format to exfat and everthing should will be fine and there should be no issues .