Ost-files with вЂњThis computer onlyвЂќ foldersДЄs said before, ost-files are вЂњonly a cacheвЂќ. Selecting a different pst-file can lead to a corrupt mail profile. When you do, make sure that you select the correct pst-file when Outlook asks you for the location of the (now missing) pst-file. However, renaming a pst-file is not recommended when it is still associated with an email account. When you have multiple POP3 accounts, you can configure them to also deliver to this pst-file even when the email address is different. In the end, this really is only just a name and not a limitation in any way. Starting with Outlook 2010, new pst-files, which are created when an account is being configured, are named after the email address of the account it is associated with.

For more on this see: Backup and Restore all Outlook data. Proper pst-backup files are created when you close Outlook and copy the pst-file to a safe backup location. However, you donвЂ™t have to use AutoArchive if you donвЂ™t want to and living without an archive.pst is perfectly healthy. By default, AutoArchive is disabled and it only gets created when you enable it. When you donвЂ™t have an archive.pst file, donвЂ™t worry. It definitely isnвЂ™t!ДЄrchive.pst is the default name which Archive or AutoArchive uses to move (not copy!) your older items to. pst-backupsДЄ misconception which sometimes comes up is that the archive.pst is a backup. For more details see: About the Outlook PST-File. If you are unsure, always take a look into the pst-file first by opening them from within Outlook via: Pst-files which are associated with a POP3 account can not be disconnected from Outlook without first assigning that account to another pst-file or Exchange mailbox.Д«lindingly deleting pst-files is never recommended as they will most likely contain all your mail, calendar appointments, contacts and more. Note: When you disconnect a pst-file, you must also close or restart Outlook before the lock on the file will be released. Outlook 2010 / 2013 / 2016 / 2019 / Office 365ДЇile-> Account Settings-> Account SettingsвЂ¦-> tab Data Files.You can create these on your own and move items to them or use the Archive or AutoArchive feature to automate the moving process based on the date/age property of your email.ДЄrchive pst-files can be created, opened and disconnected via: When a pst-file isnвЂ™t directly associated with a mail account (POP3 or IMAP), we refer to them as archives. pst-archivesД«asically, all pst-files are equal They store their data in the same way and can be reopened on other computers with Outlook. These folder are marked with вЂњThis computer onlyвЂќ.Д¬lick: Jump to information about ost-files Pst-files vs. As of Outlook 2013, IMAP accounts are also cached in ost-files.ДЄnother exception is that some folders within an ost-file do not sync with the mail server. The exception here is that Outlook 2010 and previous also used pst-files to cache the contents of IMAP accounts. The mail server basically holds the вЂњmaster copyвЂќ and the ost-file is вЂњonly a local cacheвЂќ. In the case of the last, the вЂњactualвЂќ copy will remain on the mail server and any local changes that you make or new item that you create are also synched to the mail server. The main difference between these two file types is that pst-files are being used for вЂњactualвЂќ storage and ost-files are being used for вЂњcachedвЂќ storage. Opening ost-files or converting ost-files into pst-files.Ost-files with вЂњThis computer onlyвЂќ folders.However, there are so many little exceptions to this which can make all the difference which makes things hard again.Д«elow is a short overview of the main differences and the most important exceptions you should know about before you start moving around, rename or delete pst-files or ost-files. Understanding the differences between pst-files and ost-files isnвЂ™t that hard nor should it be hard to determine whether youвЂ™ll still need it or not.

Which ones should I keep and which ones can I delete? What are the differences between these pst-files and ost-files? Some of these files are named after an email address, some are listed multiple times with a (2) or (3) behind it.

When going over some large files on my computer, I came across quite a few of pst-files and ost-files in various locations.

Outlook 2016 archive vs delete