When using a MSHOST based connection for your SAP systems, you may observe following error during both SAP System RFC Connection Test and SAP Process Server startup:
Connection Failed: RFC: Logon group "PUBLIC" not found by message server on host ...
1) In SAP navigate to SMLG, doubleclick the Logon group and verify that property Ext. RFC-enabled has been checked
2) When the above was verified, and you are still facing the error, then verify if the issue is related to 'SAP Note 1888038 - Logon Group can not be found'
This FAQ applies to RMJ