HOW TO: Exchange - Delete and Recreate Outlook’s OST File for Outlook 2007, 2010 and 2013 View The Full Article This guide explains how to delete and recreate your Outlook OST file in Outlook 2007, 2010 and 2013. This process is normally a good step to try if you notice that emails are being delivered to your Xmail inbox, but they are not being downloaded to your Outlook client. Before you attempt this process, please be aware of these notes: This process could take over an hour if you keep excessive amounts of mail in your mailbox. 10,000 messages or more It is recommended that you be connected via a wired connection wireless connections could extend the time to download your mailbox data. During the download process, your Outlook will be sluggish, and some mail may be unavailable until completed. Delete Outlookand39s OST File Close your Outlook completely. Copy the following to Windowand39s StartRunuserprofileLocal SettingsApplication dataMicrosoftOutlook Delete the existing outlook.ost files. Restart Outlook. This willcreate a new OST file. Note: Canand39t see file or extensions See Appendix below. Appendix Folder Options Windows 7 Follow these steps to display hidden files and folders. Open Folder Options by clicking the Start button , clicking Control Panel, clicking Appearance and Personalization, and then clicking Folder Options. Click the View tab. Under Advanced settings, click Show hidden files and folders, and then click OK. Folder Options Vista Enable the Display of File Extensions in Vista: Open a folder or open Windows Explorer. Click the Organize button to the left of the Views button as shown in the picture. Click Folder and Search Options. Click the View tab. Uncheck Hide extensions for known file types. Click OK. Folder Options XP Enable the Display of File Extensions in XP: Open a folder or open Windows Explorer. Click the Tools button. Click Folder Options. Click the View tab. Uncheck Hide extensions for known file types. Click OK.