When
using a Microsoft Exchange Server e-mail account
You must restart Microsoft Outlook to switch between working online and offline.
If you have not already done so, create an Offline Folder file (.ost) (Offline Folder file: The file on your hard disk that contains offline folders. The offline folder file has an .ost extension. You can create it automatically when you set up Outlook or when you first make a folder available offline.).
On the Tools menu, click E-Mail Accounts, click View or change existing e-mail accounts, and then click Next.
In the Outlook processes e-mail for these accounts in the following order list, click Microsoft Exchange Server, and then click Change.
Click More Settings.
Click the Advanced tab, and then click Offline Folder File Settings.
In the File box, type the path to the file you want to use as the .ost file.
The default file name is Outlook.ost. If this file already exists, you are prompted for a new name.
On the Tools menu, click E-mail Accounts, click View or change existing e-mail accounts, and then click Next.
In the Outlook processes e-mail for these accounts in the following order list, click Microsoft Exchange Server, and then click Change.
Click More Settings.
Do one of the following:
To always start Outlook offline, click Manually control connection state, and then click Work offline and use dial-up networking.
To choose each time you start Outlook whether to work offline or online, click Manually control connection state, and then select the Choose the connection type when starting check box.
To always connect to the network, click Manually control connection state, and then click Connect with the network.
To have Outlook automatically detect whether you can connect or not, click Automatically detect connection state. If Outlook is unable to connect with your server, it opens in offline mode automatically.
Note To specify the amount of time to wait for a response from the server before you are notified to retry or work offline, type a number in the Seconds until server connection timeout box.
When
using an Exchange Server e-mail account in Cached Exchange Mode
This feature requires you to be using a Microsoft Exchange Server e-mail account in Cached Exchange Mode.
On the File menu, click Work Offline.
Notes
When you are online, Outlook sends and receives messages immediately for Exchange, IMAP (IMAP (Internet Message Access Protocol): Unlike Internet e-mail protocols such as POP3, IMAP creates folders on a server to store/organize messages for retrieval by other computers. You can read message headers only and select which messages to download.), and HTTP e-mail accounts. For POP3 (POP3: A common protocol that is used to retrieve e-mail messages from an Internet e-mail server.) e-mail accounts, messages are sent immediately if the Send immediately when connected check box is selected on the Mail Setup tab (Tools menu, Options command). When offline all accounts use the scheduling send/receive time in the Send/Receive Groups dialog box.
When you are online, Outlook checks recipient names against any LDAP (Lightweight Directory Access Protocol (LDAP): A protocol that provides access to Internet Directories.) servers that you use, and any IMAP folders that you use are available.
When you are offline, Outlook connects to the server only when you specify. Outlook does not check LDAP servers for recipient names, and IMAP folders are not available.