Jared, I blogged about this 12c oerr.bat: "To use it, you need to set s_oraclehome to the same as %oracle_home%, set perl5lib to %s_oraclehome%\perl and copy at least oraus.msg from any Linux/UNIX Oracle box, which is missing in %oracle_home%\rdbms\mesg" (from http://yong321.freeshell.org/freeware/Windowsoerr.html) You have to have *.msg files copied from somewhere else, at least for Oracle 12.1.0.1. (I didn't install 12.1.0.2 to check it.) Yong Huang