To change a dynamic disk back to a basic disk using a command line

1. Back up all volumes on the disk you want to convert from dynamic to basic.
2. Open a command prompt and type diskpart.
3. At the DISKPART prompt, type list disk. Make note of the disk number you want to convert to basic.
4. At the DISKPART prompt, type select disk <disknumber>.
5. At the DISKPART prompt, type detail disk <disknumber>.
6. For each volume on the disk, at the DISKPART prompt, type select volume= <volumenumber> and then type delete volume.
7. At the DISKPART prompt, type select disk <disknumber>. Specify the disk number of the disk that you want to convert to a basic disk.
8. At the DISKPART prompt, type convert basic.