As has already been explained to you, you can only have up to four primary partitions on your hard drive.
Delete what's after your C drive then create a new extended partition in the resulting unallocated space.
Alternatively you could just extend your C drive to take up the empty space.
Partition Wizard is used by many of us and is a method we recommend.
Partition Wizard : Use the Bootable CD
partition wizard shows the 95GB ubuntu partition as logical whereas Windows Disk management shows this as primary
Windows only recognizes a small number of partition types as logical, and the rest as primary (or unknown), so if you created it with another tool (or under Ubuntu) as a logical partition, it's going to depend on what the actual partition type that was used to create the partition was, and which tool created it. Windows says it's primary, so Windows won't let you create another primary partition.
I would think you would be able to grow the C: partition into that space with the Windows disk management.
If you want to use it for the partition on the other side of it, I think you would need to use partition wizard.
I'm not sure he can simply extend C to the right because that free space is inside an extended partition.
Cluberti is right.
Because Windows already 'sees' four primary partitions you cannot create another one.
Everything to the right of the C drive needs to be unallocated space, and then you can create a fourth extended partition on it.
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