You can change the disk’s partition table format.
Right click on the disk (largest rectangle) with partitions inside and select Convert to MBR.
Specify the number (up to 4) of adjacent GPT partitions that will be converted to Primary Partitions, then press OK.
All other partitions will be placed inside Extended partition and converted to Logical Partitions.
You can now preview your changes.
Press Apply operations, then – Apply.
Right click on the disk (largest rectangle) with partitions inside and select Convert to GPT.
The resulting partition layout will have no extended/logical partitions. All existing primary and logical partitions will be converted to to GPT partitions.
You can now preview your changes.
Press Apply operations, then – Apply.
Hard Disk Manager for Mac, HowTos: Mac OS X
Tags: gpt, HDM for Mac, mac, mbr