How to create, compact, compare or delete offline folders in Outlook

How do I create an offline (.OST) folder? What do I do if I need to compact an offline folder? How do I repair an .OST file offline?

These are common questions we receive from Outlook® users. If these questions ring true for you, then you’re in luck.  We tackle each of the questions below and provide some helpful resources you can use to address these common challenges.

How to create an offline (.OST) folder

Offline folders are replicas of folders that can be found in your inbox on the computer that is running Microsoft® Exchange.  This makes it possible to take a folder from a server location and work on files within that folder when you’re not connected to the network. When you re-connect to the network, you can then update the folders to ensure the files within both folders are identical.

So, how do you go about creating an offline (.OST) folder?

To create an offline folder, follow the steps below:

  1. In Outlook 2007: Open the Tools menu                                                                                                                                      In Outlook 2010/2013: Open the File tab on the Ribbon, click on Info, and choose Account Settings
  1. Click on Account Settings,  then double-click on Microsoft Exchange
  2. Click on More Settings
  3. Click on the Advanced tab and then click on Offline Folder File Settings (in Outlook 2013: Outlook Data File Settings)
  4. In the File box, type the path to the file that you want to use as the (.ost) file and click on OK. The default name is Outlook.ost. If this file already exists, you will be prompted to create a new name.

If you see the message below, click OK:

  1. Click on OKNext, and then click on Finish.

Please note: Outlook must be connected to the Exchange server for the initial creation and synchronization of the Offline Folder file.

 How to compact an offline (.OST) folder

Check out the video below for simple instructions on how to compact an offline folder:

How to repair an offline (.OST) folder

To help ease the process of repairing an offline (.OST) folder, we’ve created a PowerShell script that will walk you through the repair process. Here’s how to use it:

  1. Quit Outlook if it is running.
  2. Double-click on Scanost.exe, located at drive:\Program Files\Microsoft Office\OFFICE12 or drive:\Program Files\Common Files\System\MSMAPI\LocaleID folder – where LocaleID is the locale identifier (LCID) for the installation of Microsoft Office. The LCID for English – United States is 1033.
    If you set up Outlook to prompt for a profile, the tool will also prompt you for one. In the Profile Name list, click on the profile that contains the .ost you want to check.
    If you are prompted to Connect or Work Offline, click on Connect.
  3. Select the options you want.
    To have the tool automatically resolve discrepancies it finds during the scan, select the Repair Errors check box. If this check box is cleared, the tool will log the problems but not make the necessary corrections.
  4. Click on Begin Scan.

To view the scan log, start Outlook, and then open the Deleted Items folder. The tool does not scan the Deleted Items folder. Any problems will be noted in a message with the subject “OST Integrity Check.”

Visit our Knowledge Base to learn more about how to create, compact and repair offline folders. If you still have questions, give us a call at 800-379-7729.

About The Intermedia Team

Intermedia's Office in the Cloud™ delivers essential IT services for SMBs and the partners who serve them — including hosted Exchange, Hosted PBX, SecuriSync file sync and share, security, mobility and more.