Deinstalling the Oracle software from Windows

Deinstalling the Software

How to Deinstall All Oracle Software

1. If you have already installed Oracle software, use Oracle Database Configuration Assistant to delete all current instances. Make sure that the necessary services are started in Control Panel Services before doing this.
2. Stop all Oracle-related services in the Services control panel.

3. Deinstall all Oracle products, using the appropriate installers.
(using Oracle Universal installer)
4. Delete all Oracle software directories, including the inventory files in the C:\PROGRAM FILES\ORACLE directory.

(when deleting oci.dll: encounter access denial problem. After deleting the registry entry and reboot the system, it can be manuallly deleted)

How to Uninstall Additional Software
1. Deinstall the following additional software:
JDeveloper
Apache
JDK

Checking the Registry
How to Check Registry Entries
1. Select Start > Run, enter REGEDIT, and click OK.
2. At the Windows NT Registry Editor, expand the HKEY_LOCAL_MACHINE\SOFTWARE registry item.
3. Delete the ORACLE key.
4. Expand the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services registry item.
5. Delete all keys that begin with ORACLE.
6. Expand the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\Application registry item.
7. Delete all keys that begin with ORACLE.
8. Repeat steps 5 through 8 for any other ControlSet references in your register that contain ORACLE keys.

Checking Environment Variables
How to Check Environment Variables
1.
Select Start > Settings > Control Panel and double-click System.
2.
Delete all Oracle-related environment variables (especially any ORACLE_HOME variables).
3.
Delete all Oracle-related paths from the PATH variable.
4.
Delete any reference to the JDK directory from the PATH variable.