Converts an empty basic disk with the GUID partition table (GPT) partition style to a basic disk with the master boot record ...

Converts an empty basic disk with the GUID partition table (GPT) partition     style to a basic disk with the master boot record (MBR) partition style.  Syntax:  CONVERT MBR [NOERR]      NOERR       For scripting only. When an error is encountered, DiskPart                 continues to process commands as if the error did not occur.                 Without the NOERR parameter, an error causes DiskPart to exit                 with an error code.      A basic GPT disk must be selected for this operation to succeed.      Important:          The disk must be empty to convert it to an MBR disk. Back up your data,         and then delete all partitions or volumes before converting the disk.  Example:      CONVERT MBR