This can leave you with a PST file that just gets larger and larger, taking up more of your hard drive space. At this point, the best method is to export the emails you want to save to a new PST file. This PST file will not contain any of the deleted emails and so is much smaller. You can them make this PST file your primary data file, and delete your old bloated PST file.
How to Shrink your Outlook Data File (PST)
Repeat steps 13 and 14 for each email account. Once you have tested your new (smaller!) mailbox and have made sure that everything works, you can delete your old PST file.
