Then follow the above steps to archive that folder. Pro Tip: You can also create a new folder and move all emails with large attachments to this folder. However, the data stored in this folder is stored locally and not synched with your mailbox. This creates a PST file at the selected location and a folder in your Outlook profile. Click on Browse to select a save location and then click OK.Navigate to File > Account Settings > Account Settings.After compacting the OST file, you can’t recover the deleted emails. Also, check the Deleted Items folder and restore any important emails that you may require or delete mistakenly. NOTE: Use this option after deleting the items from the Deleted Items folder. It helps users to compress the oversized or large OST file and reduces the overall OST file size by removing the deleted entries from the file permanently. However, you can also use the built-in option to compact the OST file manually. Method 1: Use ‘Compact Now’ Option in Outlookīy default, Outlook compacts the OST file once the ‘unused space’ (White Space) reaches 20% of the file size. Methods to Compact OST Fileīelow are a few methods that you may follow to compact the Outlook OST file. Besides saving storage space, it will help you improve Outlook performance and resolve sync errors. Thus, it’s important to regularly compact the OST file to reduce and control its size. Although you can change the location of the Outlook OST file to a different drive or folder, if the OST file size grows larger, it won’t resolve the problems caused by an oversized OST file. The size of OST may grow significantly over time, as you send and receive emails, which could be a problem as an oversized OST file can lead to the following problems,īy default, the OST file is stored in a different folder than the installation directory. OST (Offline Storage Table) is an Outlook data file that stores an offline copy of your mailbox items such as emails, attachments, contacts, calendar, tasks, notes, etc. Method 3: Move Mail Items from OST to PST or Archive Folder.Method 2: Use ‘Mailbox Cleanup’ Option in Outlook.Method 1: Use ‘Compact Now’ Option in Outlook.

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