I see this is an old thread, but I am encountering the same problem as originally posted. I have configured the sql agent job step properties page but I continue to receive the "could not set..." error.

/FILE "S:\ETL\PROJECTS\Hermes Profile Load\Hermes_Profile_Load\Hermes_Profile_Load\Hermes_Profile_Load.dtsx" /MAXCONCURRENT " -1 " /CHECKPOINTING OFF /SET "\Package.Variables[User::MaxBatch].Properties[value]";500 /REPORTING E

Are there other dependencies on this working? Protection level settings? Package Configurations mappings? I've tried varieties of everything I can think of.

Thanks,