Upgrade Outlook PST File Downloader - Version 2.1 Upgrade Outlook PST File - SysTools PST Upgrade tool to upgrade Outlook PST File and convert from ANSI to Unicode PST file format. ANSI to Unicode conversion is very useful for Outlook users this utility helps users to increase Outlook mailbox size. Microsoft Outlook 2007/2010 is newer and latest version of Outlook including some feature and new user interface. User can store more data in Outlook 2007/2010; using our PST Upgrade software user can easily upgrade PST for Outlook 2003/2007/2010. Use PST upgrade tool to upgrade Outlook personal folders you can easily upgrade or degrade Outlook PST files and convert that PST files into Unicode or ANSI format. Outlook PST conversion tool is very beneficial tool to upgrade or rid of corruption problem. ANSI (Outlook97, Outlook2000 and 2002) poses 2GB limitation on PST files, if your PST file becomes large than 2GB then your PST file become corrupted automatically, but Unicode (Outlook 2003, Outlook 2007 and 2010) poses 20GB limitation of PST file. You can increase the size of PST with PST conversion Tool.PST converter software