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I did not create this work, it belongs to Microsoft:

http://support.microsoft.com/kb/289987/

 

How to Manually Start PST Compaction

  1. On the File menu, click Data File Management.
  2. Click to select your Personal Folder, and then click Settings.
  3. On the General tab, click Compact Now.
  4. Click OK, and then click Close.

How to Manually Start OST Compaction

Use one of the following methods:

Method 1: Microsoft Office Outlook 2007

  1. Delete any items that you do not want to keep, and then empty the Deleted Items folder.
  2. On the Tools menu, click Account Settings.
  3. In the list, select Microsoft Exchange Server, and then click Change.
  4. Click More Settings.
  5. On the Advanced tab, click Offline Folder File Settings.
  6. Click Compact Now.

Method 2: Microsoft Office Outlook 2003 and earlier versions of Outlook

  1. On the Tools menu, click to select E-mail Accounts.
  2. Click View or change existing e-mail account, and then click Next.
  3. Click Microsoft Exchange Server, and then click Change.
  4. Click More Settings.
  5. On the Advanced tab, click Offline Folder File Settings.
  6. Click Compact Now.
  7. When the compact operation is finished, click OK twice.
  8. Click Next, and then click Finish.

APPLIES TO
  • Microsoft Office Outlook 2007
  • Microsoft Office Outlook 2003
  • Microsoft Outlook 2002 Standard Edition