I did a really dumb thing. cfdisk threw an error at me saying "FATAL ERROR: Bad primary partition 3: Partition ends in the final partial cylinder", so I installed Partition Table Doctor to see if I could fix the problem. When the program started up, it told me there were problems with my partitions, and asked if I wanted them fixed (cannot remember real message, but I believe it had something to do with the cylinder boundaries), so, blindly, without thinking of the consequences, I did.
Now, my system will not boot. I tried booting from the Windows 7 installation CD. I went to install a fresh copy, but it said that "No drives were found". I then opened up diskpart. According to diskpart, there is only one partition, containing one volume, assigned the letter "C". Before, I had four partitions! It is also saying that the file system is RAW.
Is there any way I can fix this? I have important data that I do not want to lose.
Later on... I tried fdisk with the option -l, which lists the partition table(s), and this is what I got:
Ignoring extra extended partition 4 Disk /dev/sda: 250.1 GB, 250059350016 bytes 255 heads, 64 sectors/track, 30401 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x163df116 Device Boot Start End Blocks Id System /dev/sda1 6 18 102400 7 HPFS/NTFS Partition 1 does not end on cylinder boundary. /dev/sda2 18 7851 62918572+ 7 HPFS/NTFS /dev/sda3 13073 30402 139196416 f W95 Ext'd (LBA) /dev/sda3 13073 30402 139196416 f W95 Ext'd (LBA) /dev/sda3 13073 30403 139203193 7 HPFS/NTFS
I don't know if this will help, but it's extra information, at least.
Also, this is how I had my partitions:
40MB (Unallocated) 100MB (System Reserved) 60GB (Windows, C:) 40GB (Was reserved for secondary OS) ~132GB (Home, E:)