When a session is started to connect to a cross domain application, such as TSO, using a VTAM generic resource error N20205 SELECTED APPLICATION IS INACTIVE may sometimes occur.
Why does N20205 SELECTED APPLICATION IS INACTIVE message occur?
When a session is started from MAI, a DEFLOGON is required. By default, the deflogon definition is set with APPST=YES requiring an INQUIRE APPSTAT on the application to access. If the VTAM definition refers to a generic resource indicated by a trailer asterisk, then the inquiry may fail to determine the application status mostly in cross domain.
The solution consists of setting APPST=NO to disable the INQUIRE APPSTAT prior to the logon.