Windows 2000 Roaming Profile Cache Cleanup

In Microsoft Windows 2000, roaming user profiles are designed to download to the local computer at logon and synchronize back to the network share upon logoff. By default, a local copy of this profile remains saved on the local hard drive to speed up future logons. To manage and clean up this cached data upon logoff, Windows 2000 relies on a built-in Group Policy mechanism known as "Delete cached copies of roaming profiles," which modifies the local system registry to automate the deletion of local profile directories.

The Cleanup Mechanism

When a user logs off a Windows 2000 machine, the profile engine within the Winlogon and Userenv.dll architecture handles the transition. If profile cleanup is enabled, the operating system executes the following steps:

  1. Profile Synchronization: The local profile data is compared with and written back to the central network share to ensure that changes made during the session are preserved.
  2. Policy Evaluation: The system evaluates the DeleteRoamingCache policy flag.
  3. Local Profile Purge: Once the network synchronization is verified and all open registry handles under HKEY_CURRENT_USER are successfully closed and unloaded, the operating system deletes the local copy of the profile folder located in C:\Documents and Settings\%username%.

Enabling the Mechanism via Group Policy

The primary administrative method to enforce this behavior across an Active Directory domain or on a standalone machine is through the Group Policy Object Editor:

  • Policy Path: Computer Configuration > Administrative Templates > System > Logon (or User Profiles depending on service pack level).
  • Policy Setting: Delete cached copies of roaming profiles
  • Setting State: Enabled

When set to "Enabled," Windows 2000 ensures that no roaming user profiles persist on the local hard drive once users log off.

The Underlying Registry Value

Group Policy implements this mechanism by creating or modifying a specific entry in the Windows Registry:

  • Hive: HKEY_LOCAL_MACHINE
  • Key: \SOFTWARE\Policies\Microsoft\Windows\System
  • Value Name: DeleteRoamingCache
  • Data Type: REG_DWORD
  • Value Data: 1 (A value of 1 activates automatic deletion; 0 maintains default caching behavior).

Purpose and Considerations

This cleanup mechanism is primarily used on shared workstations, public kiosks, and terminal servers where disk space is limited or where local caching poses a security risk. Because the entire profile must be downloaded anew during each subsequent logon, using this policy increases network traffic and logon times, trading bandwidth and speed for local storage conservation and data isolation.