This blog is especially for the users who are annoyed due to the large-sized Outlook mailbox which resulting in the reduction of performance of the MS Outlook. An oversized MS Outlook mailbox slows down the system performance and makes it tough to prevent corruption issue in PST file. In this kind of situation, users require a solution to reduce the size of their mailbox ASAP. So, we considered this issue and come up with this blog. You can use the "Split PST Tool". Using this secure software, you can easily reduce Outlook Mailbox size without deleting.