We usually choose compact option to reduce the size of the .pst file. There are a lot of advantages and in the same way disadvantages in using this option.
Most of them might think, as what exactly does it mean to compact Outlook data files, and why one should choose it?
As we all know Microsoft Outlook stores email messages, task, contacts, journals, appointments etc in a file called .pst file, every Outlook data item (email message, task, contact, etc.) occupies space in a .pst file.
Whenever we delete an Outlook item in a .pst file, the item goes to Outlooks Deleted Items folder. The deleted item still takes up some space in the .pst file; those deleted items can be easily recovered as they are still physically present.
From our point of view, the item is completely gone and it can’t be recovered using any normal means. And the item is deleted from the .pst file too. But the space it occupied is still unavailable for other uses. This means that, unless something happens, your .pst files will get bigger and bigger over time, even if you keep the same number of items in Outlook.
Here the Compact option comes into picture. Compacting Outlook data files reclaims the space that is unavailable because it was previously occupied by an item. This can greatly reduce the amount of space that the .pst file occupies on your hard drive, and helps Outlook function proficiently.
The advantage of using compact option is that it successfully reduces the .pst file size by permanently deleting the deleted Outlook items.
Before compacting, if you have lost any of your important Outlook items either by accident deletion or due to corruption you can easily recover outlook pst using an appropriate recovery tool like Remo Recover Outlook (pst). The same applies if you have lost emails from Outlook express. You can easily recover outlook express emails using Remo Recover Outlook Express.
If you realize that you have accidentally deleted an email after compacting, then there are no chances of recovering those lost emails as they have got permanently erased.