If you’re experiencing this issue in Masthead, you’re in the right place. This issue only allows Administrators or the person who installed Masthead to see the Masthead navigation menu.
What causes this issue?
Masthead requires an Office 365 Global Administrator to grant the application permission to be used in your tenancy. If this step in the process does not complete successfully, Masthead will only be visible to administrators and not the rest of the users in the tenancy.
How do I fix it?
Luckily, the solution is pretty simple. To fix this issue, open a new private window (Incognito in Chrome) and head over to Masthead. Click Sign Up and authenticate with a Global Admin account for your tenancy. You should receive a prompt to consent for permissions that Masthead needs. Please note that doing this will not actually sign you up twice since you’ve already signed up. This should resolve the issue.
Why do I need to do this?
Masthead is an Office 365 application that installs into your SharePoint Online sites. To keep your data secure we ensure that every user calling our Masthead service is authenticated and belongs to your tenancy. To be able to do this we need to have our application installed into your organization. This is what performing the steps above is accomplishing.