Welcome to Technical Journey: 2014

How to Uninstall Oracle 10g from windows 7 completely

Here I am gonna show you how to uninstall Oracle client software completely from the system. Most of the guys fear about this :-). Just have a look and follow the same steps while uninstalling Oracle from your system:

1.1 Stopping Oracle Services on Windows

To stop Windows services:

Open the Services control panel and from the Start menu, choose Control Panel, then Administrative Tools, then Services.
If any Oracle services (names begin with Oracle or Ora) exist and have the status Started, then select each of the services, and click Stop.
Click Close to exit the Services window.
Exit the Control Panel.

1.2 Removing Oracle Database Client with Oracle Universal Installer

Oracle Universal Installer creates Windows services for Oracle components during installation. However, Oracle Universal Installer does not delete all the services created by Oracle Net Configuration Assistant.

To remove components on a Windows computer with Oracle Universal Installer:

Ensure that you first follow the instructions in "Stopping Oracle Services on Windows".
Start Oracle Universal Installer. The start procedure depends on which version of Oracle Database Client you installed.
1. If you installed the Administrator, Runtime, or Custom versions of Oracle Database Client, then Oracle Universal Installer was also installed. From the Start menu, choosePrograms, then Oracle - HOME_NAME, then Oracle Installation Products, then Universal Installer. The Welcome screen for Oracle Universal Installer appears.
2. If you installed the Instant Client version of Oracle Database Client, Oracle Universal Installer was not installed. Instead, run it from your installation media or the installation directory you created for downloaded or copied installation files.
3. To start Oracle Universal Installer from the installation media, insert the CD labeled Oracle Database Client. The Autorun screen automatically appears.
  If the Autorun screen does not appear, from the Start menu, choose Run, and then enter the following command:
```
DRIVE_LETTER:\autorun\autorun.exe
```
  Choose Install/Deinstall Products from the Autorun screen.
4. To start Oracle Universal Installer from your installation directory, double-click setup.exe.
Click the Deinstall Products button.
The Inventory screen appears.
Select the Oracle home you wish to remove. Expand the tree of installed components only if you want to remove selected components of an Oracle home.
For example, if you installed Oracle Database Client with the Runtime option and later installed additional components with the Custom option, then expand the Oracle home component to display all the components installed in the Oracle home.
Check the boxes of components to remove.
Click Remove.
The Confirmation screen appears.
Click Yes to remove the selected components.

Note:
A message may appear indicating that removing some components may cause other components to not function properly.

After the components are removed from your computer, the Inventory screen appears without the removed components.
Click Close to close the Inventory screen.
Click Cancel to exit Oracle Universal Installer.
Click Yes to confirm that you want to exit.
After Oracle Universal Installer exits, go to the next section to remove the remaining Oracle Database Client components.

1.3 Manually Removing the Remaining Oracle Database Client Components

1.3.1 Removing Only the Oracle Net Service Registry Key

To remove only the Oracle Net Service registry entry (if it exists):

Log in as a member of the Administrators group.
Ensure that you first follow the instructions in "Stopping Oracle Services on Windows".
From the Start menu, choose Run, and then enter the following command:
```
regedt32
```
Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services and delete the OracleHOME_NAMETNSListener registry entry.
When you ran Oracle Universal Installer to deinstall Oracle Database Client, it deleted all other Oracle Net services.
Exit the registry editor.
Restart your computer.

1.3.2 Removing All Oracle Registry Keys

To remove all Oracle registry keys from a computer (if any exist):

Caution:
These instructions remove all Oracle components, services, and registry entries from your computer. Exercise extreme care when removing registry entries. Removing incorrect entries can break your system. Any database files under ORACLE_BASE\ORACLE_HOME\DB_NAME should be deleted only after completing these instructions.

Log in as a member of the Administrators group.
Ensure that you first follow the instructions in "Stopping Oracle Services on Windows".
From the Start menu, choose Run, and enter the following command:
```
regedt32
```
Go to HKEY_CLASSES_ROOT.
Delete keys that begin with the following:
- ORAMMCPMON10
- ORCLSSO
Note:
These registry keys do not appear if you installed Instant Client.
Go to HKEY_LOCAL_MACHINE\SOFTWARE.
Delete the ORACLE Group key.
If you installed Oracle Services for Microsoft Transaction Server, go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services \Eventlog\Application.
Delete the Oracle Services for Microsoft Transaction Server key.
Go to HKEY_CURRENT_USER\Software.
Delete all Oracle keys, including Oracle-HOME_NAME entries under: Microsoft\Windows\CurrentVersion\Explorer\MenuOrder\Start Menu\Programs.
Exit the Registry Editor.
Restart your computer.

1.4 Updating the PATH Environment Variable Path

Check the PATH environment variable and remove any Oracle entries.

From the Start menu, choose Settings, then Control Panel, then System. Select the Advanced tab and then click Environment Variables.
Select the system variable PATH and edit it to remove any Oracle entries.
For example, remove Oracle entries that contain ORACLE_BASE\ORACLE_HOME in the Path variable. You may see a Path variable that contains entries similar to the following:
```
ORACLE_BASE\ORACLE_HOME\bin;ORACLE_BASE\ORACLE_HOME\jre\1.4.2\bin\client;
ORACLE_BASE\ORACLE_HOME\jre\1.4.2\bin
```
Save any changes and exit the Control Panel.

1.5 Removing Oracle Database Client from the Start Menu

Check the Start menu for any Oracle Database Client entries and remove them.
Perform the following steps:

Using My Computer or Windows Explorer, navigate to the SYSTEM_DRIVE:\Document and Settings\All Users\Start Menu\Programs folder.
Delete the Oracle - HOME_NAME folder.

You can also remove Oracle Database Client menu entries with the following instructions:

Right click the Start button to display the context menu.
Select the Explore All Users option.
Expand the Start Menu\Programs folder if necessary.
Delete the Oracle - HOME_NAME folder.

1.6 Removing Oracle Database Client Directories

After removing all Oracle Database Client registry keys and restarting the computer, delete any existing Oracle Database Client directories and files.

Using My Computer or Windows Explorer, delete the SYSTEM_DRIVE:\program files\oracle directory.
Using My Computer or Windows Explorer, delete all ORACLE_BASE directories on your hard drive.