May 1, 2018, update for Outlook 2013 (KB4018376)

This article describes update 4018376 for Microsoft Outlook 2013 that was released on May 1, 2018. This update also applies to Office Home and Student 2013 RT. This update has a prerequisite.

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2013. It doesn't apply to the Office 2013 Click-to-Run editions, such as Microsoft Office 365 Home. (How to determine?)

This update contains the following fixes and improvements:

• Assume that Outlook 2013 is connected to an IMAP server that does not support UIDPLUS IMAP extensions. Then, you move an email message, and a network error occurs. After the network is restored and Outlook 2013 is synchronized with the server, the moved email message in the .OST file is lost. To fix this issue, install this update and then follow the steps in the "Registry information" section.

• When you try to access the content of a public folder in Outlook 2013, Outlook 2013 may crash if it's connected by using MAPI/HTTP.

• This update improves the Swiss translation.

• Assume that you use Outlook 2013 for some time. Even if you have a reasonable memory usage, the contiguous free memory space is exhausted. This results in fragmented and non-rendering UI. This update enables the Large Address Aware (LAA) state for the 32-bit version of Outlook 2013. For more information, see KB 4022148.

Microsoft Update

Use Microsoft Update to automatically download and install the update.

Download Center

This update is also available for manual download and installation from the Microsoft Download Center. The updates in the Download Center can't be installed on Office Home and Student 2013 RT.

• Download update KB4018376 for 32-bit version of Outlook 2013
• Download update KB4018376 for 64-bit version of Outlook 2013

If you're not sure which platform (32-bit or 64-bit) you're running, see Am I running 32-bit or 64-bit Office? Additionally, see more information about how to download Microsoft support files.

Registry information

After you install this update, you can follow these steps to fix the email message lost issue in Outlook 2013.

Important
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 all Microsoft Office applications.
2. Start Registry Editor:
    
   • In Windows 10, go to Start, enter regedit in the Search Windows box, and then select regedit.exe in the search results.
   • In Windows 7, click Start, type regedit in the Search programs and files text box, and then click regedit.exe in the search results.
   • In Windows 8 and Windows 8.1, move your mouse to the upper-right corner, click Search, type regedit in the search text box, and then click regedit.exe in the search results.

3. Locate and then select the following registry subkey:

   HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\IMAP\

4. On the Edit menu, point to New, and then click DWORD Value.
5. Type IMAPUIDRefactor, and then press Enter.
6. In the Details pane, right-click IMAPUIDRefactor, and then click Modify.

7. In the Value data box, type 1, and then click OK.

8. Exit Registry Editor.

Prerequisites

To apply this update, you must have Microsoft Office 2013 Service Pack 1 installed.

Restart information

You may have to restart the computer after you install this update.

To determine whether your Office installation is Click-to-Run or MSI-based, follow these steps:

1. Start an Office 2013 application, such as Microsoft Word 2013.
2. On the File menu, select Account.
3. For Office 2013 Click-to-Run installations, an Update Options item is displayed. For MSI-based installations, the Update Options item isn't displayed.

Office 2013 Click-to-Run installation	MSI-based Office 2013

How to uninstall this update

Windows 10

1. Go to Start, enter View Installed Updates in the Search Windows box, and then press Enter.
2. In the list of updates, locate and then select update KB4018376, and then select Uninstall.

Windows 8 and Windows 8.1

1. Swipe in from the right edge of the screen, and then tap Search. If you're using a mouse, point to the lower-right corner of the screen, and then select Search.
2. Enter windows update, select Windows Update, and then select Installed Updates.
3. In the list of updates, locate and then select update KB4018376, and then select Uninstall.

Windows 7

1. Go to Start, enter Run, and then select Run.
2. Enter Appwiz.cpl, and then select OK.
3. Select View installed updates.
4. In the list of updates, locate and then select update KB4018376, and then select Uninstall.

Learn about the standard terminology that Microsoft uses to describe software updates.

The Office System TechCenter contains the latest administrative updates and strategic deployment resources for all versions of Office.

The English (United States) version of this software update installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

x86

x64