Installation Error

Dear Manger Technical support team,

we need your help to fix the following installation Error my college is trying to install the Desktop edition and every time she getting the following Error

20.5.7:System Missing Method Exception: Method not found: ‘!!0
system.Array.Empty()’.
at Manager.Application Data.Get (Guide entityId)
at Manager Desktop.Program.Main(Stringargs)

appreciate your help ASAP

See Unable to launch Manager.