#Outlook 2016 sync all folders Offline#

Note that for Outlook 2013 this only applies to your own mailbox and not to any additional shared mailboxes you may have connected. In Outlook 2013 and later, you can use the Sync Slider to only cache more recent items rather than the entire mailbox. When you have some large folders, you can set Synchronization Filters to determine what gets synchronized and stored in the ost-file. Upon restarting Outlook, your mailbox will be recached in a new ost-file. To reduce the size of the ost-file, you can use the following methods:ДЄfter a major cleanup, you can choose to let Outlook recreate the ost-file instead of compacting it or awaiting automatic compression. Nonetheless, letting it grow unnecessarily large isnвЂ™t the way either. If you are on a reasonably modern computer and are using Outlook 2007 SP2 or later, your ost-file can be as large as 10GB and youвЂ™d still wonвЂ™t notice a performance hit. Reducing the size of the ost-file isnвЂ™t always that easy and not always needed either. You could compare this to zipping a large txt-file it allows for quite some compression and thus results in a smaller ost-file. This is because Outlook 2013 and later compress certain streams of text when storing it in the ost-file. When you use Outlook 2013 or later, the ost-file can actually be up to 30% smaller than the reported mailbox size. This is due to some storage inefficiency of the ost-file and the way Exchange calculates the mailbox size (Exchange 2013 and later calculates it more accurately though). The ost-file can easily be 20-30% larger than the reported mailbox size when using Outlook 2010 or previous.

This especially applies to Exchange accounts. However, even when you would disable all the additional caching and store nothing in the вЂњThis computer onlyвЂќ folders, the size of the ost-file could be quite different from the size of the mailbox. You probably now see that the mailbox size and the size of the ost-file can be quite far apart. To do this see: DonвЂ™t risk losing your Contacts and Calendar when using IMAP in Outlook 2013, 2016, 2019, or Office 365. This is because unlike pst-files, ost-files canвЂ™t always be directly restored without the use of 3rd party recovery or conversion tools such as Stellar Converter for OST.ДЇor IMAP accounts in Outlook 2013 and later, it is therefor recommended to set an additional pst-file as the default data store for the non-mail folders. If you store data in these folders, it is recommended to make backups of these folders itself via an Export rather than a backup of the ost-file. For more information see: Setting the Sent Items folder for IMAP accounts in Outlook 2013, 2016, 2019 and Office 365.

* This applies only to some IMAP servers for which Outlook cannot automatically determine the special folders. The following folders do not sync with the IMAP mail server: These folders are marked with вЂњThis computer onlyвЂќ. However, the ost-file could additionally contain some unique data which isnвЂ™t being synched with the mail server. In this case, the ost-file is also mainly used for caching the mailbox data which is stored on the IMAP mail server. In Outlook 2013, 2016, 2019 and Office 365, IMAP accounts use ost-files as well. What is stored in the ost-file of an IMAP account? Shared folders of additional mailboxes linked to your Exchange account.Hidden items and other вЂњoverheadвЂќ as found in a pst-file.Your mailbox data (mail, calendar, contacts, tasks, notes and journal folders).In general, the following is stored in the ost-file: In addition, it acts as a foundation for several features in Outlook which couldnвЂ™t be used otherwise such as Instant Search, the People Pane and Conversation View.

#Outlook 2016 sync all folders Offline#

The main purpose of this cache is to reduce network traffic, reduce the payload on the Exchange server(s) and provide offline availability. What is stored in the ost-file of an Exchange account?ДЇirst of all, the ost-file of an Exchange account is only a cache of data which is stored on the Exchange server(s). What is being stored in an ost-file also depends on whether you are using an Exchange or IMAP account. When you use Outlook 2013, 2016, 2019 or Office 365, the ost-file can also actually be smaller than your mailbox. Of course, in most cases, your own mailbox does make up the large part of the ost-file but there is much more stored in there which can be quite big or even bigger as well!

Looking at the size of your ost-file isnвЂ™t really representative for the size of your mailbox. What accounts for this difference and how can I make my ost-file smaller? However, when I look at my ost-file, I see that it is over 3GB in size. We have a maximum mailbox size of 2GB and IвЂ™m currently using 700MB of it.