I am using an old Outlook PST file that I recently discovered is in ANSI format. The issue is that it has a size limitation (around 2GB), and I am worried it might get corrupted once it reaches that limit. I have read that newer Outlook versions use Unicode PST files, which support much larger sizes and are more reliable. Can someone please guide me on how to upgrade or convert my ANSI PST file to Unicode PST without losing any data? Also, I like to understand why this upgrade is important and in what situations it becomes necessary. What is the best method or tool to perform this upgrade safely?