When you use Microsoft Outlook with Microsoft Exchange Server, your messages, contacts, appointments, and journal entries are stored in a mailbox located on the server. This information is stored in a Personal Folder file or Outlook Data file (PST). At the same time, Outlook configures an exact replica of this PST file in your system to enable you work offline. This file is named Offline Outlook Data file (OST). By default, this OST file is created in the Windows directory. Usually there is no need to keep a backup of the OST file as it is an exact replica of PST file. It is possible to move OST file from its default location to another, though it’s not usually required. But when your C drive is full, you can think of moving the OST file to another location.
In outlook, when we specify a new location for the OST file, a new OST file is created there. There is no need for you to move the old file to the new location as the Outlook automatically re-creates the OST file there. But by moving the old OST file to the new one, we can save the time required for downloading it. In Outlook 2010, the following steps can be used to move an OST file created for Exchange mailbox. But ensure that you exit the Outlook application completely before starting.
1.Go to Control Panel and double-click Mail.
2.Click Show Profiles, select the Exchange account profile, and finally click Properties.
3.Go to Data Files tab, select the Exchange account and click Settings.
4.Go to the Advanced tab, uncheck Use Cached Exchange Mode checkbox and click OK.
5.Again click OK when the message “You must restart Outlook for these changes to take effect” is displayed.
6.Again, click Settings, go to Advanced tab and click Outlook Data File Settings button
7.Click the button Disable Offline Use ; click Yes when “do you want to continue” alert appears.
8.Again click the Outlook Data File Settings button, select “I want to create a file”, click Browse to browse the required location, and finally click Open.
10.Now in the Microsoft Exchange dialogue box, check the checkbox Use Cached Exchange Mode and click OK.
11.Click OK when “You must restart Outlook for these changes to take effect” message displays.
12.Close the dialogue boxes Account Settings and Mail setup.
13.Finally click OK in the Mail dialogue box.
However this method cannot be used to relocate the OST file in Outlook 2013 because the Browse button on the Outlook Data File settings dialogue box is disabled. However you can try a different approach to relocate the OST files in Outlook 2013.
1.Go to Control Panel, search for the mail item (mail item labeled Microsoft Outlook 2013 or Microsoft Outlook 15), and open it.
2.Add a new profile by following the steps given below:
i.Click the Add button
ii.Enter Profile Name and click OK.
iii.Ensure that your account name is displayed in the Email Address dialogue box; click Next.
iv.Check the Change account Settings checkbox after the account has been set up; click Next.
v.Click the button More Settings in the Server Settings section.