Manual Oracle Uninstall

A number of people have contacted me regarding problems uninstalling Oracle products. The two methods listed below should only be used as a last resort and will remove *all* Oracle software allowing a re-install. If you make any mistakes they can be quite destructive so be careful.

• Windows
• UNIX

Windows

In the past I've had many problems uninstalling all Oracle products from Windows systems. Here's my last resort method:

• Uninstall all Oracle components using the Oracle Universal Installer (OUI).
• Run regedit.exe and delete the HKEY_LOCAL_MACHINE/SOFTWARE/Oracle key. This contains registry entires for all Oracle products.
• If you are running 64-bit Windows, you should also delete the HKEY_LOCAL_MACHINE/SOFTWARE/Wow6432Node/Oracle key if it exists.
• Delete any references to Oracle services left behind in the following part of the registry (HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/Ora*). It should be pretty obvious which ones relate to Oracle.
• Reboot your machine.
• Delete the "C:\Oracle" directory, or whatever directory is your ORACLE_BASE.
• Delete the "C:\Program Files\Oracle" directory.
• If you are running 64-bit Wiindows, you should also delete the "C:\Program Files (x86)\Oracle" directory.
• Remove any Oracle-related subdirectories from the "C:\ProgramData\Microsoft\Windows\Start Menu\Programs\" directory.
• Empty the contents of your "C:\temp" directory.
• Empty your recycle bin.

At this point your machine will be as clean of Oracle components as it can be without a complete OS reinstall.
Remember, manually editing your registry can be very destructive and force an OS reinstall so only do it as a last resort.
If some DLLs can't be deleted, try renaming them, the after a reboot delete them.

UNIX

Uninstalling all products from UNIX is a lot more consistent. If you do need to resort to a manual uninstall you should do something like:

• Uninstall all Oracle components using the Oracle Universal Installer (OUI).
• Stop any outstanding processes using the appropriate utilities.
  

  # oemctl stop oms user/password
  # agentctl stop
  # lsnrctl stop

  Alternatively you can kill them using the kill -9 pid command as the root user.
• Delete the files and directories below the $ORACLE_HOME.
  

  # cd $ORACLE_HOME
  # rm -Rf *

• With the exception of the product directory, delete directories below the $ORACLE_BASE.

  # cd $ORACLE_BASE
  # rm -Rf admin doc jre o*

• Delete the /etc/oratab file. If using 9iAS delete the /etc/emtab file also.

  # rm /etc/oratab /etc/emtab