How to reduce the size of your Outlook Personal Folders

If you use Personal Folders (.pst files) in Outlook, most of the time you simply add more stuff making them bigger. But if you delete items from a Personal Folder file to save storage space, you may not realise there are 2 very important things to do before you'll get the space back on your hard disk:

  1. Right click on the Deleted Items folder within your Personal Folder and choose Empty "Deleted Items" Folder
  2. Right-click on the topmost folder in your Personal Folders' file and select Properties, then click the Advanced button before clicking the Compact Now button. Outlook will compact your .pst file freeing up the space on your hard disk that it no longer needs. Note: if you've deleted a lot of stuff the compacting can take a little time so please be patient.

Item 1 on this list seems fairly obvious, but is easily overlooked. Item 2 is less obvious. "So why is it needed?" I hear you scream. In order to minimise processing delays Outlook doesn't automatically downsize .pst files when items are removed. This is because most .pst files simply grow and grow as items are added. Only the dedicated few are efficient enough to delete items they no longer need. Indeed, you could argue that deleting unwanted items from a .pst file is an inefficient use of times these days now that storage is so affordable. But it's still good practice to tidy up your Personal Folders every once in a while. Your local data retention legislation may even require you to do this if your Personal Folder contains old personal information (like contact details) about others.

Next time you dust off your .pst file remember to follow the two steps above. Your hard disk will thank you for it.