As I am learning Oracle in the Windows environment, I noticed that I do not have to set ORACLE_HOME. Am I missing something? Thanks! H:\>echo %ORACLE_HOME% %ORACLE_HOME% H:\>sqlplus system/manager@triwebb SQL*Plus: Release 10.1.0.4.2 - Production on Mon Jan 18 15:23:00 2010 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options SQL> exit Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64 bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options H:\>set ALLUSERSPROFILE=C:\Documents and Settings\All Users APPDATA=C:\Documents and Settings\rxu\Application Data CATALINA_HOME=C:\Tomcat5028 CLASSPATH=C:\j2sdk1.4.2_06;C:\Tomcat5028\webapps\WEB-INF\classes CLIENTNAME=BB011257 ClusterLog=C:\WINDOWS\Cluster\cluster.log CommonProgramFiles=C:\Program Files\Common Files COMPUTERNAME=DRAGON ComSpec=C:\WINDOWS\system32\cmd.exe FP_NO_HOST_CHECK=NO HOMEDRIVE=H: HOMEPATH=\ HOMESHARE=\\cbcsrv1\users$\rxu JAVA_HOME=C:\j2sdk1.4.2_06 LOGONSERVER=\\CBCADC2 NUMBER_OF_PROCESSORS=8 OS=Windows_NT Path=E:\OraIAS\jdk\jre\bin\classic;E:\OraIAS\jdk\jre\bin;E:\OraIAS\bin;E:\OraIAS \jlib;E:\OraPortal\bin;E:\OraPortal\jlib;D:\oracle\product\10.2.0\db_1\bin;C:\WI NDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Dell\SysMgt\ RAC5;C:\Program Files\Dell\SysMgt\oma\bin;%OMPATH%;C:\j2sdk1.4.2_06\bin PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH PROCESSOR_ARCHITECTURE=x86 PROCESSOR_IDENTIFIER=x86 Family 6 Model 15 Stepping 11, GenuineIntel PROCESSOR_LEVEL=6 PROCESSOR_REVISION=0f0b ProgramFiles=C:\Program Files PROMPT=$P$G SESSIONNAME=RDP-Tcp#129 SystemDrive=C: SystemRoot=C:\WINDOWS TEMP=C:\DOCUME~1\rxu\LOCALS~1\Temp\1 TMP=C:\DOCUME~1\rxu\LOCALS~1\Temp\1 USERDNSDOMAIN=CARTERBC.NET USERDOMAIN=CARTERBC USERNAME=rxu USERPROFILE=C:\Documents and Settings\rxu windir=C:\WINDOWS H:\>