The email using security is calling Java but it is explicitly calling the JAVA.EXE that we provide in the JAVA\BIN folder under DBAMFG (or EVOERP) folder.  Can you run any of the JDBC programs?  SM-T, BM-N, DE-A?

Most of the programs in Evo and DBA are written in the TAS language which has been used since the original DOS DBA program (TAS 3) and has evolved to the current Evo version (TAS 7).  DBA Classic is TAS 5.  
 
As we have tried to address customer requests we have come across some challenges that can not be met within the TAS language so we have introduced a handful of programs written in Java and using JDBC to connect to the database when a database connection is needed.  The JDBC settings are established at SM-T.  The secure email is one of the Java programs as are BM-N, DE-A, SH-R, GL-R, SO-I and a few others.

Does Test Settings at SM-T work?

You need to go to Internet Explorer - Tools - Internet Options - Security - Local Intranet and make your server a trusted site to make the popup go away.