Recommendations for Using Offline Files

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

By using Offline Files, you can manage user data more efficiently while enhancing users’ access to their files and folders. When combined with Folder Redirection, Offline Files improves availability; when combined with Synchronization, Offline Files increases the reliability of content.

Files and Folders You Can Make Available Offline

You can make available for offline use any shared files or folders on a Microsoft network. You can make files available offline from any computer that supports Server Message Block-based file and printer sharing, including Microsoft® Windows® 95, Microsoft® Windows® 98, Windows NT 4.0, and the Windows Server 2003 family.

You can set up shared folders so that every network file the user opens in that shared folder is available offline. Alternatively, you can specify which network files are made available offline. Table 7.15 shows typical Offline Files caching settings for each redirected folder.

Note

• If you make a shortcut to a file available offline, that file is made available offline. However, if you make a shortcut to a folder available offline, the contents of that folder are not available offline.

Table 7.15   Offline Files Settings

Offline Files Caching Options

In the Windows Server 2003 family, Offline Files is, by default, not enabled. When enabled, the following three types of Offline Files caching are available:

• Only the files that users specify will be available offline (previously called Manual Caching for Documents). Provides offline access to only those files on a network share that have been manually selected. Manual caching for documents is the default option when you set up a shared folder to use offline.

• All files and programs that users open from the share will be automatically available offline (previously called Automatic Caching for Documents and Automatic Caching for Programs). Selecting this option makes every file that someone opens from your shared folder available offline. However, only those files that have been opened are available offline.

• Files or programs from the share will not be available offline. Selecting this option prevents users from storing files offline.

In Windows XP and Windows Server 2003, the default behavior is to cache all redirected folders automatically. Even if you specify manual caching for a redirected folder, the folder is still subject to automatic caching. To disable this default behavior, enable the Do not automatically make redirected folders available offline policy setting, available in User Configuration\Administrative Templates\Network\Offline Files. If you enable this policy setting, the users must manually select the files to be made available offline.

Combining Offline Files with EFS

When you use Offline Files, you can specify that offline files are encrypted. If you choose to encrypt offline files, only the files on your local computer are encrypted. The files on the network are not encrypted, nor are the files encrypted as they traverse the network.

The Encrypt offline files to secure data setting is disabled under the following conditions:

• You are not an administrator on the computer.

• The local drive is not NTFS or does not support encryption.

• A system administrator has implemented an encryption policy for Offline Caching.

• The Offline Files technology is not available in Windows XP Home Edition.

• In the Windows Server 2003 family, Offline Caching is not enabled by default.

Deploying Offline Files on Terminal Services Clients

Multi-user Terminal Services disables Offline Files on computers that run Windows Server 2003. Terminal Services on Windows XP Professional is always single user, but Terminal Services on servers is multi-user by default. To use Terminal Services and Offline Files together on servers, set the value of the AllowMultipleTSSessions registry entry to 0. This entry is found in the following registry subkey**:** HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon

Caution

• Do not edit the registry unless you have no alternative. The registry editor bypasses standard safeguards, allowing settings that can damage your system, or even require you to reinstall Windows. If you must edit the registry, back it up first and see the Windows Server 2003 Resource Kit Registry Reference on the Windows Server 2003 Deployment Kit companion CD or at https://www.microsoft.com/reskit.

Offline Files and Synchronization Manager

The copies of offline files that are stored in the Offline Files data store are kept up to date by Synchronization Manager. The Synchronization Manager tool is invoked when users with roaming user profiles log on, log off, or access selected files or folders.

Caching Offline Files

Offline Files notifies users when the status of the network connection changes. A message notifies users when they are offline, and the users can continue working with the files. When they work offline, users can still browse network drives and shared folders that are set up for Offline Files. A red X appears over any disconnected network drives that are not currently available. For more information about their network connection status, users can click the Offline Files icon in the notification area.

When the network connection is restored, any changes the user made while working offline are updated to the network. If other users have made changes to the same file, options are offered to the users for resolving the version conflict. For more information, see "Handling file conflicts" in Help and Support Center for Windows Server 2003.

Forcing Synchronization

A user who is concerned about losing network connectivity can force synchronization to ensure that local copies of network files are current.

You can use Synchronization Manager to perform periodic synchronizations to ensure that users’ offline files are kept current.

Note

• To keep offline files current with minimal interruption to users, schedule offline files to be synchronized whenever users’ computers are idle.

Synchronizing Offline Files

If you configure Offline Files, you need to decide the appropriate time to synchronize offline files. You also have a choice of two methods, full or quick. For a full synchronization, enable the Synchronize all offline files before logging off policy setting. Disabling this policy causes aquick synchronization to be performed when the user logs off.

A full synchronization ensures that you have the most current versions of every network file that has been made available offline. A quick synchronization ensures that you have complete versions of all your offline files, even if they are not the most current versions.

In Windows Server 2003, the Synchronize all offline files when logging on policy setting mirrors the Synchronize all offline files before logging off policy setting. Both policy settings are available in both User Configuration and Computer Configuration under Administrative Templates\Network\Offline Files. For more information, see the Explain tab on the Properties page of each policy.

By default, the Offline Files feature is not enabled in the Windows Server 2003 family because any Terminal Services mode that allows multiple, concurrent user logon sessions is not compatible with Offline Files. Offline Files is enabled by default in Windows XP Professional and Windows 2000 Professional.

To maximize the benefits of Offline Files, the Synchronization Manager service frequently synchronizes server and client copies of any offline file. However, synchronization makes demands on file system and network resources.