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Chapter 28. Tips and Hints for Oracle 10g on Red Hat Enterprise Linux

To reinstall Oracle 10g after a failed installation attempt, you might want to execute the following commands. Make sure you first used the "De-installation" option in the OUI. 
su - root
export ORACLE_HOME=/u01/app/oracle/product/10.1.0/db_1
. $ORACLE_HOME/bin/localconfig delete
The above line stops the Oracle CSS daemon and deletes the configuration. 
rm -rf /u01/app/oracle/*

rm -f /etc/oraInst.loc /etc/oratab
rm -rf /etc/oracle
rm -f /etc/inittab.cssd
rm -f /usr/local/bin/coraenv /usr/local/bin/dbhome /usr/local/bin/oraenv
Make sure you comment out ORACLE_HOME from ~oracle/.bash_profile.