Error when running a bat file

Question

Can someone tell me what this error means; "ORA-12560: TNS:protocol adapter error"
I had Oracle XE on my Windows XP Pro SP3, but I also install the EE of Oracle which I haven't setup yet. Originally when I run this .bat file by double clicking on it, "setup_distran_database.bat", everything worked fine. But now, I am getting tghe above error. Not sure if it was because I installed Oracle EE.
This is the .bat file:
*@ECHO off*
*:: Ayo Ojikutu*
*:: Using Murach's Oracle SQL and PL/SQL*
*:: and Mike Murach & Associates, Inc. example*
*:: Nov 11, 2011*
*:: Uses SQL*Plus utility to run the SQL scripts that create*
*:: and populate the tables in the AP, OM, and EX schemas.*
*:: If necessary, edit the username/password*
sqlplus system/passwordhere @setup_distran_database*
*:: Display a message about the log file*
ECHO.
ECHO For details, check the setup_distran_database.log file in the current directory.
ECHO.
*:: Display 'press any key to continue' message*
PAUSE

Answer 1

"ORA-12560: TNS:protocol adapter error"
Not sure if it was because I installed Oracle EE.Most probably yes, Windows has the last installed product environment. Try setting XE environment before running sqlplus, something likeset ORACLE_SID=XE
set ORACLE_HOME=<XE Oracle Home>
set PATH=<XE Oracle Home\bin>;%PATH%
sqlplus .....