Hmm, I do apologise; I seem to have done some maths completely wrong somewhere along the line there. This is the correct command: sudo dd if=/dev/sda bs=512 skip=60275880 count=1 | od -tx1 -Ax To answer your question on IRC, there's usually one extended boot record per extended partition. If you're able to follow this kind of thing through for yourself, perhaps it would help if I gave you the tools to do the job yourself. (If you can't follow this, you can ignore the rest of this comment and just follow my instructions above, and we'll do it the slow way.) What I'm doing here is looking for the extended partition record in your master boot record; the result of doing all of this is that I should be able to plug the information into a test file here and run parted on it to (hopefully) simulate your problem. The four partition records in each boot record begin at offset 0x1BE, and occupy 16 bytes each. The fifth byte of each partition record is the partition type, and is either 0x05, 0x0F, or 0x85 for an extended partition. In your case we can see that the first extended partition is described by this partition record, starting at offset 0x1EE: 00 fe ff ff 0f fe ff ff a8 bc 97 03 da b9 61 0a The ninth to twelfth bytes identify the first sector of the extended partition; they're least-significant-byte-first, so you can convert to decimal like this: $ echo $((0x0397BCA8)) 60275880 The extended boot records are almost exactly the same for our purposes, except that the sector addresses there are relative to the start of the first extended boot record. This means that in your case you need to add 60275880 to the address you get from each extended boot record. If a record doesn't end with "55 aa", then you've made a mistake and should go back and recheck your figures. Here's a full worked example for my disk: $ sudo fdisk -l /dev/sda Disk /dev/sda: 80.0 GB, 80026361856 bytes 255 heads, 63 sectors/track, 9729 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x10000000 Device Boot Start End Blocks Id System /dev/sda1 1 14 112423+ de Dell Utility /dev/sda2 15 276 2097152 7 HPFS/NTFS Partition 2 does not end on cylinder boundary. /dev/sda3 * 276 2707 19531250 7 HPFS/NTFS /dev/sda4 2708 9729 56404215 5 Extended /dev/sda5 2708 7571 39070048+ 83 Linux /dev/sda6 9437 9729 2353491 82 Linux swap / Solaris /dev/sda7 7572 9436 14980581 83 Linux Partition table entries are not in disk order $ sudo od -Ax -tx1 -N512 /dev/sda 000000 eb 48 90 d0 bc 00 7c 8e c0 8e d8 be 00 7c bf 00 000010 06 b9 00 02 fc f3 a4 50 68 1c 06 cb fb b9 04 00 000020 bd be 07 80 7e 00 00 7c 0b 0f 85 10 01 83 c5 10 000030 e2 f1 cd 18 88 56 00 55 c6 46 11 05 c6 46 03 02 000040 ff 00 00 20 01 00 00 00 00 02 fa 90 90 f6 c2 80 000050 75 02 b2 80 ea 59 7c 00 00 31 c0 8e d8 8e d0 bc 000060 00 20 fb a0 40 7c 3c ff 74 02 88 c2 52 be 7f 7d 000070 e8 34 01 f6 c2 80 74 54 b4 41 bb aa 55 cd 13 5a 000080 52 72 49 81 fb 55 aa 75 43 a0 41 7c 84 c0 75 05 000090 83 e1 01 74 37 66 8b 4c 10 be 05 7c c6 44 ff 01 0000a0 66 8b 1e 44 7c c7 04 10 00 c7 44 02 01 00 66 89 0000b0 5c 08 c7 44 06 00 70 66 31 c0 89 44 04 66 89 44 0000c0 0c b4 42 cd 13 72 05 bb 00 70 eb 7d b4 08 cd 13 0000d0 73 0a f6 c2 80 0f 84 ea 00 e9 8d 00 be 05 7c c6 0000e0 44 ff 00 66 31 c0 88 f0 40 66 89 44 04 31 d2 88 0000f0 ca c1 e2 02 88 e8 88 f4 40 89 44 08 31 c0 88 d0 000100 c0 e8 02 66 89 04 66 a1 44 7c 66 31 d2 66 f7 34 000110 88 54 0a 66 31 d2 66 f7 74 04 88 54 0b 89 44 0c 000120 3b 44 08 7d 3c 8a 54 0d c0 e2 06 8a 4c 0a fe c1 000130 08 d1 8a 6c 0c 5a 8a 74 0b bb 00 70 8e c3 31 db 000140 b8 01 02 cd 13 72 2a 8c c3 8e 06 48 7c 60 1e b9 000150 00 01 8e db 31 f6 31 ff fc f3 a5 1f 61 ff 26 42 000160 7c be 85 7d e8 40 00 eb 0e be 8a 7d e8 38 00 eb 000170 06 be 94 7d e8 30 00 be 99 7d e8 2a 00 eb fe 47 000180 52 55 42 20 00 47 65 6f 6d 00 48 61 72 64 20 44 000190 69 73 6b 00 52 65 61 64 00 20 45 72 72 6f 72 00 0001a0 bb 01 00 b4 0e cd 10 ac 3c 00 75 f4 c3 00 00 00 0001b0 00 00 00 00 00 00 00 00 00 00 00 10 00 00 00 01 0001c0 01 00 de fe 3f 0d 3f 00 00 00 4f 6e 03 00 00 05 0001d0 38 0e 07 1b 48 13 00 70 03 00 00 00 40 00 80 1b 0001e0 49 13 07 fe ff ff 00 70 43 00 e4 0b 54 02 00 fe 0001f0 ff ff 05 fe ff ff d3 92 97 02 ee 51 b9 06 55 aa 000200 $ echo $((0x029792D3)) 43487955 $ sudo dd if=/dev/sda bs=512 skip=43487955 count=1 | od -tx1 -Ax 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.000108604 s, 4.7 MB/s 000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fe 0001c0 ff ff 83 fe ff ff 3f 00 00 00 c1 52 a8 04 00 fe 0001d0 ff ff 05 fe ff ff 09 7f 71 06 e5 d2 47 00 00 00 0001e0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa 000200 $ echo $((0x06717F09 + 43487955)) 151589340 $ sudo dd if=/dev/sda bs=512 skip=151589340 count=1 | od -tx1 -Ax 1+0 records in 1+0 records out 512 bytes (512 B) copied, 7.0331e-05 s, 7.3 MB/s 000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fe 0001c0 ff ff 82 fe ff ff 3f 00 00 00 a6 d2 47 00 00 fe 0001d0 ff ff 05 fe ff ff 00 53 a8 04 09 2c c9 01 00 00 0001e0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa 000200 $ echo $((0x04A85300 + 43487955)) 121628115 $ sudo dd if=/dev/sda bs=512 skip=121628115 count=1 | od -tx1 -Ax 1+0 records in 1+0 records out 512 bytes (512 B) copied, 6.6489e-05 s, 7.7 MB/s 000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0001b0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fe 0001c0 ff ff 83 fe ff ff 3f 00 00 00 ca 2b c9 01 00 00 0001d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 * 0001f0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa 000200 $