"Your Outlook data file cannot be configured" error when you try to start Outlook 2013


When you try to start Microsoft Outlook 2013, you receive the following error messages, and Outlook does not start:

Your Outlook data file cannot be configured. <path of .ost file>

Outlook Data File error message

Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened.

Cannot start Microsoft Outlook error message


This issue occurs because following registry data is configured on the computer:

Key: HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\PST
DWORD: UseLegacyCacheSize
Value data: 1


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. We will provide more information in this article when the information becomes available.


Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.
  1. Exit Outlook.
  2. Start Registry Editor. To do this, use one of the following procedures, as appropriate for your version of Windows:
    • Windows 8: Press the Windows Key + R to open a Run dialog box. Type regedit.exe, and then press OK.
    • Windows 7: Click Start, type regedit.exe in the search box, and then press Enter.
  3. In Registry Editor, locate the following subkey in the registry:
  4. Locate and then right-click the following value, and then click Delete.
  5. Click Yes to confirm the value deletion.
  6. Exit Registry Editor.

Article ID: 3072598 - Last Review: Jun 26, 2015 - Revision: 1

Microsoft Outlook 2013