If you use Microsoft Outlook for your email and have been using it for a long time, chances are that your PST file has grown quite large. This can cause problems such as slower performance, difficulty in backing up the file, and an increased risk of corruption. I know a safe method to reduce the size of your PST file by compressing and compacting it is by using Ignissta software which helps you to Split PST files
into single PST files without any data loss. This software has the ability to remove duplicate emails items while merging multiple PST files into one. Use Ignissta Splitter and Merger
software. This is a perfect software to Split PST files to Office 365 platform while keeping your data secure and uncorrupted at the same time. This tool also helps to combine Outlook emails, contact, calendar, outlook archives etc.