Article ID: 947300 - View products that this article applies to.
After you install Windows Server 2008 or Windows Vista Service Pack 1 (SP1) in unallocated space on a GPT disk, the Microsoft Reserved (MSR) partition is not automatically created. As a result, you cannot convert a basic GPT disk to a dynamic disk.
An MSR partition is not created automatically when you install Windows Server 2008 or Windows Vista SP1 to unallocated space on a GPT disk that already contains an Extensible Firmware Interface (EFI) system partition.
To prevent this, use the Disk Configuration window during installation to create a partition in the unallocated spaces. The installation will automatically reserve space for an MSR partition. If this problem occurs after you have completed the installation, use one of the following options:
Option 1If unallocated space exists before the data partitions are created, use the Diskpart command prompt utility to create a 128 MB MSR partition. For more information about the Diskpart command prompt utility, click the following article number to view the article in the Microsoft Knowledge Base:
(https://support.microsoft.com/kb/300415/ )A Description of the Diskpart Command-Line Utility
Option 2If you cannot create an MSR before the data partitions are created, follow these steps:
Steps to reproduce the problemCreate an EFI system partition on a GPT disk that has no other partitions. Install Windows Server 2008 or Windows Vista SP1 in unallocated space on the disk by using Windows Setup. Make sure that the following conditions are true:
Article ID: 947300 - Last Review: June 30, 2008 - Revision: 2.0