Summary: Microsoft Outlook provides an option to work offline when the network is unavailable, slow, or infeasible. It allows users to continue their work without hindrance, but it stops outgoing and incoming messages. In this blog, we have discussed offline mode, opening Outlook in Offline Mode, and switching between Offline Mode and Online Mode.
Microsoft Outlook is a popular email client widely used for accessing Exchange and Office 365 email accounts. However, one can also use the Outlook desktop client to access any IMAP or POP3-based email account.
When it comes to adding and configuring an Exchange or Office 365 email account, Outlook offers an exclusive feature called Cached Exchange Mode, also known as Offline Mode. It enables users to access their emails even when the system is offline or the network is unreliable.
The best part is that users never notice a glitch while using Outlook in Offline Mode. This is because the mail items are stored in an Outlook Storage Table or Offline Folder file (.ost) at a default location based on the Outlook and Windows version. To know more, refer to our previous post on OST file location.
Below you will learn how to open Microsoft Outlook in Offline Mode and work offline. You will also learn to switch between work offline and online modes in Outlook.
Steps to Open Microsoft Outlook in Offline Mode
By default, if you add an Outlook.com, Office 365, or Exchange email account in Outlook, the email profile is set up in the Cached Exchange Mode, and an Offline Folder (OST) file is created. OST stores a synchronized copy of mailbox items on the local computer to access their emails, make changes to Outlook, draft an email or send messages. The changes are stored in the local OST file and synchronized later with the mailbox server when the connectivity is restored.
But if you use a POP3 email account, such as Gmail, in Outlook, the profile isn’t set up in Offline Mode. As a result, you need an active connection to continue working with your emails. However, Outlook also provides an option known as Work Offline.
Follow these steps to switch to Offline Mode,
- Open Outlook and go to File> Account Settings> Account Settings…
- Select the email you want to switch to offline mode and click Change
- If your profile belongs to Exchange or Office 365, Cached Exchange Mode should be enabled. If not, click the Use Cached Exchange Mode checkbox.
- You may also choose how much mail to keep offline in the local OST file.
- Click Next> OK and restart Outlook.
Your profile is now switched to Offline Mode. This mode is highly recommended for Office 365 and Exchange account users.
Outlook users can also quickly switch between Work Offline and Work Online with one click. The steps are as follow,
- Open Outlook and go to Send/Receive tab
- Click the Work Offline option.
This will disconnect your Outlook from the mail server, but you can keep working without interruptions.
The difference between Offline Mode and Work Offline is that the former allows you to send and receive emails and works on two-way synchronization. The changes are saved locally in the OST file and frequently synced with the mailbox server. Also, this option is only available for Outlook.com, Office 365, and Exchange email accounts.
The latter disconnects from the server and saves changes to the local File. The changes are synced once you go online. This works for all email accounts.
When you enable Work Offline, a cross icon is displayed on Outlook, and the status bar display working Offline.
To switch back to online mode, click the Work Offline option again. The status should change to connected.
Conclusion
You can open Microsoft Office in offline mode by changing the email account settings. But if you use Exchange, Outlook.com, or Office 365, your profile is already set in Offline Mode unless your organization has set a policy to enable online mode or you have disabled the Offline Mode. While setting up Offline Mode in Outlook, you may choose the number of mail items you want to keep offline. For example, you may choose between 3 days to 24 months.
You can also choose to keep all mail items offline. However, changing the number of mail items to 1 year or more will synchronize a large number of mail items. This can take time and increase local OST file size, which may cause inconsistencies and slow outlook performance. Moreover, your OST may become inaccessible if it exceeds the recommended limit. If space is low on your device and you send/receive or exchange multiple emails every day, keep 1-month data offline. However, if the OST becomes inaccessible or orphaned, you can always use an OST to PST converter tool, such as Stellar Converter for OST, to extract email items from your OST and save them to Outlook importable PST format.
