it was discussed i8n MSFS Forum.
I had two problem s:
1- the down loaded AIRBUS H file was corrupted .
2- we should ignore the advice of the game that the aircraft is not installed .
Further information on the installation and running of the downloaded Airbus H, It was found in the FSMS 2020 contents section and marked as UNINSTALLED, click on it to install it says WAITING.
I do not understand waiting for what?
The internet is there and running !