I am getting an exception with outlook while sending an email: ‘The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)’

Hi,
I am getting following exception with outlook while sending an email . Any suggestions please ?

20.4.0-beta.718

Message: Property accessor ‘Account’ on object ‘UiPath.Mail.Activities.Business.OutlookApplicationCard’ threw the following exception:‘The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)’