Outlook allows you to create Outlook Data Files (personal folders or .pst files) to give you additional storage capability without using your quota on the Office 365 server.  You can create additional folders to help with managing your mail.  You may wish to organize your mail into folders for each project you are working on or all messages from your boss in one folder.  Personal folders can be used to save or archive e-mail that you no longer wish to keep on the server.  They are also a good way to reduce the amount of space you are using towards your quota.

The Personal Folders or .pst files can be stored locally on your hard drive or on a file server (e.g., your H: drive).  If you store them on your hard drive, you will need to make sure to back them up on a regular basis.   NOTE:  you must exit Outlook every night if you store your .pst files on the network drive (H: drive), otherwise, the files will not get backed up.  NOTE:  Microsoft does not support .pst files being stored on a network drive.

If you are moving to a new computer and your personal folders are stored locally, you will need to save them to a network drive or CD before you switch.

  1. Choose File tab | Info | Account Settings | Account Settings | Data Files tab | Click Add
  2. Choose the location to save your file on the "Save in" panel. This can be your local hard drive (C: drive) or a location on your network server (H: drive). The default location is C:\Documents and Settings\Local Settings\Application Data\Microsoft\Outlook. The default file name is: My Outlook Data File(1).pst
    NOTE: ITS recommends that you first create a folder outside of the default Outlook directory to save your .pst files (e.g., H:\Exchange or C:\Exchange). This is important to easily locate your .pst files and is especially important if you move to a new computer and need to move a Windows profile. 
  3. Click OK.
  4. Select the new .pst file then click Settings... to modify the Outlook Data File name or set the password.
    General tab. file name highlighted. OK button highlighted.
  5. Click OK. The .pst folder is now created. There are two default folders in your new .pst folder -- Deleted Items and Search Folders. You can now create new folders for storing mail.
  1. Right click on the .pst folder name and choose New Folder.
  2. Type the folder name and select the location (your .pst folder).
  3. Click OK.
    Once you have created folders for storing mail you can move messages to those folders. There are a couple of different ways to do this.
  1. Right click on the message you wish to move.
  2. Choose Move to Folder
  3. Select the folder name (.pst folder) and click OK.
  1. Choose File | Move to folder or click the Move to Folder icon
  2. Choose the folder name from the list of recently used folders or click Move to Folder
  3. Select the folder name (.pst folder) and click OK.

Additional Information

 When you delete items from a Personal Folders file, your file size will not decrease until you compact the file.

  1. Choose File | Data File Management
  2. Click the file to compact. 
  3. Click Settings
  4. Click Compact Now.
  1. Right click on the .pst file name.
  2. Choose Properties.
  3. Click the Advanced tab. 
  4. In the Name field, change the name of the .pst file. 
  5. Click OK to save the changes. 

If you already have personal folders and you want to find out where they are stored:

  1. Right click on the folder name. 
  2. Choose Properties.
  3. On the General tab, click on the Advanced button.
  4. The location of the personal folders is listed under the Filename field. 

NOTE: You must exit Outlook every night if you want your .pst files to backed up on the file server (e.g., your h: drive). 

NOTE:  Microsoft does not support storing personal folders on a network drive, they recommend storing on your harddrive.

There are several methods to choose from for backing up your PST files:

  1. A Microsoft utility called PST Backup that enables you to make an exact copy (in the same file format) of a .pst data file, copy the backup file to your hard drive or H: drive, and specify how often Outlook will prompt you to back up a file. You can then use the backup file to restore the current .pst file if needed. For more information on the PST Backup utility, see "Using the Microsoft Outlook Personal Folders Backup Tool".
  2. Use Microsoft Windows backup utility. A backup wizard will prompt you for: which files to backup, where to back them up (e.g., H: drive, cd drive, etc.), and how often to back them up. Manually backup the files by copying the files to your H: drive or disk.

NOTE: ITS provides limited support for these methods.

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Last updated: 
October 25, 2016