July 5, 2017, update for Outlook 2010 (KB4011042)

Applies to: Microsoft Outlook 2010


Known issues

If you have a recurring calendar item (meeting or appointment) that contains attachments in Outlook 2010, Outlook 2010 may crash when you open an occurrence of the recurring item. If you use recurring calendar items that have attachments, and you have to access individual occurrences, you should uninstall this update and use the workarounds that are listed in the Outlook known issues in the June 2017 security updates until a new fix is available. If you do not have to access individual occurrences, you can successfully open the recurring series without crashing. This is a workaround until a fix for this issue is available.

Improvements and fixes

This update fixes the following attachment issues that were reported after the release of the June update. See Outlook known issues in the June 2017 security updates for more information.

Issue 1

When you open an attachment whose file name includes an ellipsis (...) or an exclamation point (!), the files are blocked and you receive a warning message.

Issue 2

If an email message includes an attached email message, and the attached email message's subject line includes an unsafe file name extension (as listed in the Blocked attachments in Outlook Office webpage), the email attachment is blocked for recipients.

Issue 3

You receive an error message when you open attachments in an email message, a contact, or a task that's formatted as Rich Text.


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