Outlook - Managing Ost File Size

This guide explains how to check the size of an Outlook OST file and provides recommendations for managing large OST files to ensure optimal performance.

Instructions

Outlook

1. Click on File in the top-left corner.

2. Select Account Settings, then choose Account Settings again from the dropdown.

3. Under the Data Files tab, select your email account and click Open File Location.

   Open

   

4. In the file explorer window, right-click the OST file and select Properties.

5. Check the file size under Size to see if it is approaching or exceeding 49 GB.

File Explorer

1. Open File Explorer and type the following in the top search bar then press Enter.

   %localappdata%\Microsoft\Outlook
   Open

   

2. Locate the OST file, typically named with the associated email address.

3. Right-click the file and select Properties.

4. Under the General tab, check the Size field to see if it exceeds 49 GB.