Outlook Performance Series: Outlook data file (.pst or .ost file) issues - Le Café Central de DeVa - Site Home

Welcome to troubleshooting performance issues for MS Outlook 2007 Series - Part 4

If the .pst file or the .ost file shuts down incorrectly, you may receive one of the following error messages the next time that you start Outlook:

•	Error message 1: Outlook cannot open the data file `filename` until it has been checked for problems.
•	Error message 2: Microsoft Office Outlook’ exited without properly closing your Outlook data file ‘`drive`:\Users\`username`\AppData\Local\Microsoft\Outlook\outlook.ost’. ‘Microsoft Office Outlook’ must be restarted. If this error message recurs, contact support for ‘Microsoft Office Outlook’ for assistance.
•	Error message 3 : The data file `filename` was not closed properly’. This file is being checked for problems.

If you receive one or more of these error messages, you may experience performance issues until Outlook finishes the reconciliation process for the .ost file or for the .pst file. The following gear icon is displayed in the status bar while Outlook checks the data file in the background:

When this icon disappears, the .pst file or the .ost file is reconciled. If you exit Outlook while the gear icon is present, reconciliation must restart the next time that you run Outlook. It's recommended that you leave Outlook running until the gear icon disappears before you exit Outlook.

An incorrectly shut down .ost file or .pst file may occur for one of the following reasons:

•	Antivirus scanning of the file
•	Forced Microsoft Windows shutdown before the Outlook.exe process shuts down completely
•	Outlook add-ins

If you see this issue frequently, and you have to exit Outlook shortly before you shut down your computer, it may be better to shut down Windows while Outlook is still running.