Hi It works now, many appreciate for your help. Thanks.. Best Regards. --- On Mon, 11/2/09, Duy Thang Dao wrote: From: Duy Thang Dao Subject: Về: [Yaffs] A Three YEARs Problem!!!-----Can not see file afterwrite yaffs2 image on NAND To: "yichia lan" Cc: yaffs@lists.aleph1.co.uk Date: Monday, November 2, 2009, 1:18 AM Hi, You should look into the kernel source code to find the solution. For example, I am using linux kernel 2.6.29.3. Come to driver/mtd/nand/, and read into nand_base.c. You see that: static struct nand_ecclayout nand_oob_64 = {      .eccbytes = 24,      .eccpos = {             40, 41, 42, 43, 44, 45, 46, 47,             48, 49, 50, 51, 52, 53, 54, 55,             56, 57, 58, 59, 60, 61, 62, 63},      .oobfree = {          {.offset = 2,           .length = 38}} }; Is that your NAND which has 64 bytes in OOB ? And you are using this definition for your NAND ? If the offset = 2  then you can be use command "mkyaffs2image  /tmp/test/ /tmp/yaffs2.img   2". So offset = x, using: mkyaffs2image  /tmp/test/ /tmp/yaffs2.img   x Make clearly what is your definition of your NAND 's OBB. Best, regard