If you new to SharePoint 2013 like me and get confused looking for “Sign in as a Different User” menu command, don’t worry it is not there by design but we can easily bring it back.

Do the following steps to get the link back:

• Locate the file \15\TEMPLATE\CONTROLTEMPLATES\Welcome.ascx and open it for editing.
• Add the following snippet before the existing element that have id of “ID_RequestAccess”.

 Text="<%$Resources:wss,personalactions_loginasdifferentuser%>"
 Description="<%$Resources:wss,personalactions_loginasdifferentuserdescription%>"
 MenuGroupId="100"
 Sequence="100"
 UseShortId="true"
 />

Save and close the file. Now you should get the link “Sign in as Different User” back.

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