Microsoft Knowledge Base Article 842162 contains the following summary and introduction:
SUMMARYThe system volume, or SYSVOL, is a collection of folders, file system reparse points, and Group Policy settings that are replicated by the File Replication Service (FRS). Replication distributes a consistent copy of Group Policy settings and scripts among domain controllers in a domain. Member computers and domain controllers access the contents of the SYSVOL tree through two shared folders, Sysvol and Netlogon.
This article describes how to move the SYSVOL tree and its shares to a different logical or physical drive letter.
INTRODUCTIONIn the life cycle of a domain controller that is running Microsoft Windows 2000 or Microsoft Windows Server 2003, you may have to relocate the SYSVOL tree to a different logical or physical drive. You may relocate the SYSVOL tree to enhance system performance or to obtain more free disk space for the SYSVOL tree or for the FRS staging folder.
For additional information about changing the FRS staging folder to a location that is independent of the SYSVOL tree, click the following article numbers to view the articles in the Microsoft Knowledge Base:
265085 Moving FRSStagingPath requires non-authoritative restoration pre-Service Pack 3 versions of FRS
How to reset the File Replication Service staging folder to a different
To relocate a SYSVOL tree to a new drive, use one of the following options:
|•||Perform a network-based Active Directory Installation Wizard (Dcpromo.exe) demotion. Specify a new drive and path for the SYSVOL tree during promotion.|
|•||Modify the registry and manually move the SYSVOL tree to a new drive.|