I was trying to install Linux on the unallocated space on my disk and ran into some problems. After examining the disk, it appears that there are 5 primary partitions and a chunk of unallocated space.
In windows disk manager, they are all tagged as "Primary" (inluding the 1st 100MB "system reserved" parition), except for the "Unallocated space".
It seems to be a "basic" MBR disk, as evidenced by Properties->Volume in Windows. In fdisk, the disk type is listed as "dos" which also means MBR.
I know that MBR disks are limited to 4 primary partitions. So how is this possible?