When installing Microsoft App-V Server 5 as an Administrator, you get this error:
Microsoft Application Virtualization (App-V) Server 5.0 Setup
Setup lacks the privileges necessary to complete installation. Please re-run setup using elevated administrative privileges.
To fix this error, click OK, then right click the installer (when logged in as an administrative account) then click Run as Administrator. If you don’t have the Run as Administrator option, hold down Shift when right clicking the installer.