There may be items in the backup file that you might be able to recover that the Inbox Repair tool couldn't. Open the OST file as per the location provided in the table. As you open it across the File Explorer, lead to the "View" menu from the top. There, turn Outlook Login Issues Troubleshooting on the option of "File Name Extensions" to display extensions.

Repair Outlook Data Files (.pst and .ost)

This is all most people will need, searching for older items will be slower but for daily use items it will still be quick. As you close them, lead to the folder and right-click on the OST file. Once you re-open Outlook, your OST file is automatically recreated or rebuilt. If your hard drive goes through any physical damage, it will damage the data across it too. A bad sector or corrupted hard drive can cause OST inaccessibility.

Outlook - OST file recurring corruption

You surely won't be disappointed with the results of rebuilding OST. As you change the extension, relaunch Outlook connection status shows disconnected to rebuild your OST file. The first solid question that comes to mind is whether OST files are rebuildable. We are aware that OST files are directly connected to the Outlook email.

• Although there are many methods to try, a few are productive.
• The Lost and Found folder contains any folders and items recovered by the repair tool that Outlook can't place in their original structure.
• Further, the saved PST file could be accessed at any time by importing it in the Outlook profile.
• OST file corruption is a common problem faced by Outlook users like you.
• Any MS techs can contact me if they need further information or analysis.
• You might be working on something important across it when it happens.
• Only way to restore Outlook 2016 (Windows) functionality was to create a new profile; this worked, and a new OST file was created.

What are the major Reasons of OST Corruption and how to Fix it

Fwiw, responding to my original post and how we addressed it for this user - we ended up creating new Outlook profile and limiting the amount of cached mail to 2 years. If the OST still gets corrupted when you have reduced the size there is something in the mailbox causing the problem. You must re-select "Account Settings" when it opens across a drop-down menu. There, lead into the "Data Files" tab and select your OST file. After selecting the file, click on "Open File Location" to redirect to the folder.

Method 4: Use OST Repair Tool

Only way to restore Outlook 2016 (Windows) functionality was to create a new profile; this worked, and a new OST file was created. On the next screen, access the "Find File" option if you are unaware Microsoft Outlook Email Repair Tool Online of the location. If you know the location, click on the "Add File" tab and browse it.