WINDOWS 1002000 PROFESSIONAL RESOURCE KIT [Electronic resources] نسخه متنی

Configuring Offline Files for Portable Computers

Offline Files gives users access to files and folders that are on network shares even when they are disconnected from the network. It does this by storing the network version of files and folders on the local hard disk. When users are not connected to the network, they have access to the offline version of the files and folders as though they were connected to the network. When they reconnect to the network, the stored files and folders are synchronized with the network versions of the files. This section discusses configuration issues you need to consider when you are using offline files on a portable computer. For more information about configuring offline files and synchronization, see "Managing Files, Folders, and Search Methods" in this book.

Configuring Files on a Network Share for Offline Use

Before you can have access to the files on a shared network folder offline, you must specify how the files in the folder are stored in a cache on the client computer (in this case, the user's portable computer). For non-executable files, such as word processing documents, spreadsheets, and bitmaps, there are two options for storing files:

Automatic caching

Manual caching

Automatic caching makes a file available offline (creates a locally stored copy of the file) when a user opens the file on their portable computer. Automatically stored files might not always be available in the cache because Windows 2000 might remove (purge) them from the cache when the cache becomes full. Windows 2000 selects files for purging on the basis of how often they are used. Automatic caching is the most useful when you have an unreliable or unpredictable network connection. For example, if a user is working on an automatically stored file and the portable computer gets disconnected from the network, the user can continue working on the file without interruption because the file has been automatically stored on the portable computer. If a user requires that a file be available offline all of the time, the user should mark the file as Always available offline by using Windows Explorer or My Computer. For more information about making files available offline, see "Pinning Files and Folders for Offline Use" later in this chapter.

Manual caching makes a file or a folder available offline, but only when it is manually marked ("pinned"), on the user's computer. A manually stored file or folder that is not pinned on the user's computer is not available offline. Manual caching is useful for users who need access to a file or folder all of the time or for users who need access to entire folders, especially when the folder contains documents that have been created by or modified by other people. For example, manual caching works well for someone who frequently uses their portable computer away from their office without a network connection but who still needs access to a large number of files on the network. In this case, you can manually pin folders on the user's portable computer, and then those folders are available to the user when he or she is away from their office. Automatic caching is not ideal in this case because the files in the network folder are not locally stored unless the portable computer user opens each of them while the portable computer is connected to the network share.

To configure automatic or manual caching on a shared network folder

Right-click the shared folder you want to configure, and then click Sharing.

In the folder properties dialog box, click Caching.

In the Setting drop-down box, select the type of storing (caching) you want.

NOTE

---

You can also choose Automatic caching for programs, which is useful if a user runs programs from the network. This option stores a copy of a network program on the user's hard disk so they can run the program when they are offline. However, portable computer users need to be careful when they use this feature because only the program files that are executed get stored on the local computer. For example, if you run Microsoft® Word from a network share but you do not use the spell checking tool, the spell checking tool is not stored. If you then run Word when you are offline and you try to run the spell checking tool, the tool is not available. To avoid this problem, you can load all of your programs and all associated tools locally on a portable computer and not use the Automatic caching for programs option.

Pinning Files and Folders for Offline Use

If you choose manual caching for offline files, you must pin the file or folder on the user's portable computer. When you pin a file or folder, a copy of the file or folder is copied to the local cache on the portable computer. By default, all users have permission to pin files and folders. However, you can use Group Policy to change this default behavior.

To manually pin a file or folder

While you are connected to the network, select the shared network folder or file you want to make available offline.

On the File menu, click Make available offline.

NOTE

---

You can manually pin a folder or a file even when the folder or file has been configured for automatic caching. In this case, pinning forces the file or folder to be stored. Therefore, pinning has precedence over automatic caching.

When you manually pin a folder that contains subfolders, you are prompted to choose whether you want to make subfolders available offline or whether you want to make only the contents of the folder available offline. You can change this behavior by using administrative templates in Group Policy so that subfolders are always made available offline.

To make subfolders always available offline when a folder is manually pinned

From the Start menu, click Run.

Type:

gpedit.msc

Press ENTER.

In the console tree pane of the Group Policy console, under Computer Configuration, open the Administrative Templates folder, and then open the Network folder.

Click the Offline Files folder.

In the details pane, double-click Subfolders always available offline.

In the Properties dialog box, click Enabled.

You can also pin folders using the administrative templates in Group Policy. Along with other Group Policy settings, this is the best way to ensure that folders and their contents are always available offline.

To pin folders using group policy

From the Start menu, click Run.

Type:

gpedit.msc

Press ENTER.

In the view pane of the Group Policy console, under Computer Configuration, open the Administrative Templates folder and then open the Network folder.

Click the Offline Files folder.

In the details pane, double-click Administratively assigned offline files.

In the Properties dialog box, click Enabled, and then click Show.

In the Show Contents dialog box, click Add.

Enter the Universal Naming Convention (UNC) path for any folder or file you want to administratively pin. Do not enter a value for these folders. You can use environment variables in the paths.

When you administratively pin a folder using Group Policy, all files and subfolders within that folder are made available offline. As a consequence, the Make available offline menu item that appears when you right-click a shared folder or file is checked and disabled. This prevents users from manually unpinning administratively pinned files and folders, although they can still pin and unpin folders and files that have not been administratively pinned.

Users can delete offline files in the Offline Files folder even though they have been administratively pinned. However, the deleted files and folders are-stored the next time Group Policy updates policies on the computer (by default, every 90 minutes, although you can change this). Also, users can still enable, disable, and configure offline files unless you administratively restrict a user's ability to configure offline files, which you also can do by using administrative templates in Group Policy.

To prevent users from configuring offline files

From the Start menu, click Run.

Type:

gpedit.msc

Press ENTER.

In the view pane of the Group Policy console, under Computer Configuration, open the Administrative Templates folder and then open the Network folder.

Click the Offline Files folder.

In the details pane, double-click Disable user configuration of Offline Files.

In the Disable user configuration of Offline Files Properties dialog box, click Enable.

Be careful how you implement this policy. Preventing users from configuring offline files might not be appropriate for all portable computer users. For example, if a portable computer is frequently disconnected from the network and a user needs to reconfigure offline files, he or she is unable to do so. Administratively pinning folders might be enough to ensure that specific folders are always available offline and do not get unpinned or deleted from the cache by a user.

Configuring Options for Offline Files

A general overview of Offline Files options is presented earlier in this book. (See "Managing Files, Folders, and Search Methods.") Two of those options are particularly relevant to portable computer users: the size of the cache and the way Offline Files behave when network connections are disconnected.

Offline Files allows you to configure the amount of disk space that is used to store offline files (in other words, you can configure the size of the local cache). This option only affects offline files that are stored automatically; it does not affect offline files that are stored manually. Because disk space is often limited on a portable computer, you might want to modify this value if you are relying on automatic caching. By default, the value is set at 10 percent of disk size.

For manually stored files, the cache size is limited only by available disk space, up to a maximum value of 2 gigabytes (GB). This can be a problem if you are using manual caching and disk space is limited. In this case, you might want to limit the number of folders you manually store or change some folders from manual caching to automatic caching.

To change the size of the offline files cache

In Windows Explorer, open any folder that contains offline files

On the Tools menu, click Folder Options.

In the folder options dialog box, click the Offline Files tab.

Under Amount of disk space to use for temporary offline files, move the slider to change the cache size.

Offline Files also allows you to configure how lost network connections are handled. There are two options: Notify me and begin working offline, or Never allow my computer to go offline. The first option, which is the default, gives users access to offline files and folders when a connection is lost or when a connection is intentionally disabled or disconnected (for example, when a portable computer is undocked). The second option should be used carefully with portable computers because it prevents user access to offline files, whether a network connection is lost or is intentionally disabled or disconnected. In other words, if you choose the second option with a portable computer and a user disconnects the portable computer from the network, the user does not have access to any offline files. The offline files are essentially disabled. The following procedure describes how to change the way Offline Files is handled when a network connection is lost.

To change the way offline files is handled when network connections are lost

In Windows Explorer, open any folder that contains offline files.

On the Tools menu, click Folder Options.

In the folder options dialog box, click the Offline Files tab.

Click Advanced, and then choose either Notify me and begin working offline or Never allow my computer to go offline.

For portable computers that are frequently disconnected from the network, Notify me and begin working offline is the preferable setting. Because it is the system default for Offline Files, you should not have to change this option.

Configuring Synchronization for Offline Files

Synchronization ensures that any changes that are made to offline files and folders are propagated back to the network and that any changes that have occurred on the network are propagated to the user's computer. A general overview of synchronization options is presented earlier in this book. (See "Managing Files, Folders and Search Methods.") This section discusses synchronization features and options that relate specifically to portable computers.

Configuring Synchronization for Battery-Powered Computers

In order for synchronization to occur, the hard disk on a user's portable computer must be powered up so that files can be copied from the network to the local cache and files in the local cache can be copied to the network. This might not be an optimum use of power for a portable computer when it is running on battery power. Fortunately, there are configuration options that allow you to control whether synchronization occurs when a computer is running on battery power.

Enabling Synchronization During Idle

By default, offline files are not synchronized when a computer is in an idle state and it is using battery power. This is because portable computers rely on a low-power idle state to conserve battery power and you might not want to waste battery power synchronizing files. You can change this so that synchronization occurs when the computer is on idle even when the computer is running on battery power.

To enable synchronization during idle when running on battery power

From the Start menu, point to Programs point to Accessories, and then click Synchronize.

In the Items to Synchronize dialog box, click Setup.

In the Synchronization Settings dialog box, click the On Idle tab, and then click Advanced.

In the Idle Settings dialog box, click the Prevent synchronization when my computer is running on battery power check box to clear it.

Preventing Scheduled Synchronization

You can also schedule synchronization for specific days and times. Because a scheduled synchronization is often a low-priority task that consumes power, Windows 2000 allows you to prevent scheduled synchronization from running when a computer is operating under battery power.

To prevent scheduled synchronization when the computer is running on battery power

From the Start menu, point to Programs and then Accessories, and then click Synchronize.

In the Items to Synchronize dialog box, click Setup.

In the Synchronization Settings dialog box, click the Scheduled tab.

Click a scheduled task, and then click Edit.

On the Settings tab, under Power Management, click the Don't start the task if the computer is running on batteries check box.

If a scheduled synchronization is in progress and a portable computer is shifted from alternating current power to battery power, you can have Windows 2000 cancel synchronization. This might occur if scheduled synchronization starts on a docked portable computer that is using a wireless network connection and the user performs a hot-undock.

To stop scheduled synchronization when the computer is running on battery power

From the Start menu, point to Programs and then Accessories, and then click Synchronize.

In the Items to Synchronize dialog box, click Setup.

In the Synchronization Settings dialog box, click the Scheduled tab.

Click a scheduled task, and then click Edit.

On the Settings tab, under Power Management, click the Stop the task if battery mode begins check box.

If a computer is not connected to a network when scheduled synchronization occurs, you can configure Windows 2000 to connect so that synchronization can occur. This might not be desirable for portable computer users, especially if they frequently use the portable computer while it is disconnected from the network. In this case, Windows 2000 attempts to connect to the designated network, detects that the computer is not connected to the network, and then informs the user that the network is not available. By default, Windows 2000 does not connect if there is no network connection at the time of synchronization.

To enable automatic connection for scheduled synchronization

From the Start menu, point to Programs point to Accessories, and then click Synchronize.

In the Items to Synchronize dialog box, click Setup.

In the Synchronization Settings dialog box, click the Scheduled tab.

Under Current synchronization tasks, click a scheduled task, and then click Edit.

On the Synchronization Items tab, click the If my computer is not connected when this scheduled synchronization begins, automatically connect for me check box.

NOTE

---

You can also enable automatic connection during scheduled synchronization when you first schedule the synchronization.

Synchronizing Over a Slow Link

Windows 2000 does not provide a system-wide definition or threshold for a slow link; rather, Windows 2000 allows every system component to define a slow link in terms of its own capabilities and requirements. For example, one component might define a slow link as 28.8 kilobits per second (Kbps), while another might define it as 56 Kbps. For Offline Files and synchronization, a slow link is defined as any connection that operates at 64 Kbps or slower, which is the speed of a single-channel Integrated Services Digital Network (ISDN) connection. Therefore, most modem connections through telephone lines are considered slow link connections with regard to offline files synchronization. This is important because synchronization behaves differently depending on whether the network connection is considered a slow link or not.

A slow link connection affects synchronization two ways: it prevents the automatic transition of shared network folders to an online state, and it prevents newly added files from being pulled from the network share to the user's computer during synchronization. This behavior is not configurable, but it is important to know how the behavior affects portable computer users.

Transitioning from an Offline State to an Online State

After a network share has been offline to a user (for example, a server goes offline and is then brought back online, or a user undocks their portable computer and then docks it), it becomes available online for the user if three conditions are met:

No offline files from that network share are open on the user's computer.

None of the offline files from that network share have changes that need to be synchronized.

The network connection is not considered a slow link.

When all of these conditions are satisfied and a user opens a file on the network share, the user is working online on that network share. Any changes that the user makes are saved to the file on the network share as well as to the file that is stored in the Offline Files folder. When any one of these conditions is not met and a user opens a file on the network share, the user is still working offline, even though the network share is available. Any changes that the user makes are saved only to the offline version of the file.

When a user first connects to a network over a slow link connection, the user also is working offline on any shared network folders, even though the folders are available. To start working online with a shared network folder, the user must synchronize the shared network folder. Synchronization shifts the folder to an online state and pushes any offline files that have changed to the shared network folder. It does not pull files on the shared network folder to the Offline Files folder. To do this, the user must perform a second synchronization, which pulls files that have changed from the network share to the Offline Files folder.

NOTE

---

When you are using a slow link connection, a second synchronization does not pull newly created files from the network share to the Offline Files folder. To make new files on the network share available offline during a slow link connection you must manually pin the files.

Making Network Shares Available Without Synchronization

As discussed in the previous section, slow link connections can prevent a network share from coming online even though the network share is available. Although you can bring the network share online by synchronizing it, this method might not be ideal—for example, when a user's portable computer is disconnected from the network and the user requires access to a file on a shared network folder that has been made available offline, a file to which the user has made several changes offline but is not ready to synchronize with the network share. Another example is when a user is in a hurry and does not want to take the time to synchronize files—the user wants only to connect to the network, get the new file from the network share, and then log off. Windows 2000 provides a way of doing this.

To make a folder available online without synchronizing offline files

In the System Tray, click the Offline Files icon to open the Offline Files Status dialog box.

Click the Work online without synchronizing changes check box.

NOTE

---

The Offline Files icon appears in the System Tray when users are working offline.

Managing the Offline Files Folder

Portable computer users who frequently work offline might end up with hundreds of files stored in the Offline Files folder on their hard disk. Because many of these files might be out-of-date, rarely used, or no longer needed offline, you might want to delete them from the Offline Files folder (the cache) in order to maximize the available disk space. You might also want to delete files in the Offline Files folder if a network share has been deleted or is no longer available. In addition to deleting individual files, you can reinitialize the Offline Files cache, which deletes the entire contents of the Offline Files folder. Reinitializing the Offline Files cache is useful when you transfer a computer to a new user or when a user has been working offline with sensitive or proprietary documents and you want to ensure that they are no longer available offline or that they are not in the cache.

Deleting Files

There are two methods for safely removing offline files from the cache without affecting network files or folders. You can open the Offline Files folder and delete files directly from the list of offline files. This method of cleaning up the cache allows you to delete individual files regardless of where they are located on the network or of the folder in which they are contained. Also, when you delete a file this way, the file is removed from the cache regardless of whether it was manually or automatically stored.

If you remove a file from the cache and its parent folder is pinned, the file is copied to the cache the next time you synchronize offline files.

To delete files from the cache by using the offline files folder

In Windows Explorer, open a shared network folder.

On the Tools menu, click Folder Options.

In the Folder Options dialog box, click the Offline Files tab, and then click View Files.

Click the file you want to delete, and then on the File menu, click Delete.

You can also delete files on a network-share basis. This method allows you to delete batches of files according to the shared folder in which they are contained. This method also allows you to distinguish between automatically stored files and manually stored files. If you delete manually stored folders this way, the folders and the files in them are no longer be pinned. To make these files or folders available offline again, you must pin the files or folders. When you delete automatically stored files this way, you only need to open the files to make them available offline.

To delete files from the cache on a network share basis

In Windows Explorer, open a shared network folder.

On the Tools menu, click Folder Options.

In the Folder Options dialog box, click the Offline Files tab, and then click Delete Files.

In the Confirm File Delete dialog box, select the shared folders that contain the offline files that you want to delete.

Click the Delete only the temporary offline versions check box if you want to delete only the files that have been automatically stored. Click the Delete both the temporary offline versions and the versions that are always available offline check boxif you want to delete files that have been automatically stored and files that have been manually stored.

NOTE

---

Files are also deleted from the cache whenever an offline file is deleted through any usual user path, such as Windows Explorer, My Computer, the Run dialog box, or the command prompt. As soon as the user verifies that he or she wants to delete the file, the file is removed from the cache. This is not an effective way to clean up the cache because it also deletes files in the shared network folder.

Reinitializing the Cache

Reinitializing the Offline Files cache deletes all of the offline files from the Offline Files folder, and it resets the system's Offline Files database. If there are files in the cache that have changed and have not been synchronized with the network versions, the changes are lost when you reinitialize the cache. Also, this procedure requires that you restart the computer after the cache is reinitialized.

To reinitialize the offline files cache

In Windows Explorer, open a shared network folder.

On the Tools menu, click Folder Options.

In the Folder Options dialog box, click the Offline Files tab.

Press CTRL + SHIFT, and then click Delete Files.

CAUTION

---

You cannot undo the effects of reinitialization. After the cache is reinitialized, all offline files are permanently removed from the computer.