Sign in as different user menu is missing in SharePoint 2013

It’s been noted that the “Sign in as a Different User” menu command is missing in SharePoint 2013. This “Sign in as Different User” menu item is very useful when testing applications, but it can lead to some problems when opening documents. So, it may be for these reasons that the option has been removed in SharePoint 2013.

You can add the menu item back in, but I would suggest only doing this on test or development SharePoint servers.

To do this, please follow the below steps:

1.      Go to the file \15\TEMPLATE\CONTROLTEMPLATES\Welcome.ascx and open in a text editor.

2.      Add the following element before the existing element with the id of “ID_RequestAccess”

           <SharePoint:MenuItemTemplate runat="server" ID="ID_LoginAsDifferentUser"

            Text="<%$Resources:wss,personalactions_loginasdifferentuser%>"  

            Description="<%$Resources:wss,personalactions_loginasdifferentuserdescription%>" 

            MenuGroupId="100"  Sequence="100"  UseShortId="true"

           />

 3.      Save the file.

Now, go to the menu and check. It shall be displaying.

Hope this helps.