Microsoft Outlook: How to repair Outlook 2016 where File Attach menu only appears briefly when clicked.

This is a quick step by step to allow users to solve this problem on their own Admin systems.

In Outlook 2016, the Attach File menu may appear only briefly when clicked.  This issue can happen to an existing install or be present after first installation of Outlook 2016.  This article outlines the most common method used to repair this issue.

Step 1

 Close Outlook 2016. 

Step 2

Press Start and type "credentials" into the search field, and select "Credential Manager"

Step 3

When Credential Manager opens, you can see the "Generic Credentials" at the bottom.  For each one, click the down arrow icon, and select "Remove from vault."

Do this for all the entries under "Generic Credentials."

Step 4

After removing all the generic credentials, close the window.

Step 5

Open Outlook 2016.  Once signed in, you should be able to attach files again.  If you cannot, contact the Technology Service Desk or open an Incident.