In that case, the default folders are Deleted Items and Search Folders. You can add additional pst-files to separate your data between multiple files. The default folders within a pst-file for a POP3 account are Within this single file, Outlook stores all your folders and items (emails, contacts, appointments, etc…). Difference between ost-files and pst-filesĪs mentioned, when using a POP3 account, Outlook uses a PST-file to store your data in.Fixing a broken pst-file with scanpst.exe.This guide contains these basics but also more advanced and additional background information about the pst-file and how you can handle them. In other words Pst-files are pretty important to Outlook and knowing how to properly treat pst-files is one of the more important basic Outlook skills as well. Pst-files can also be used for additional storage, archives and exports, even when you are using an Exchange or /Hotmail account. Outlook 2010 and previous also used pst-files for caching IMAP data. Pst-files, when you are using a POP3 account, Outlook can’t live without them.