In this post i try to explain how we can remove Oracle 11gR2 on windows 7 platform.I see this question sometimes on OTN forum site. Please follow below steps for can remove oracle 11gR2 software on win 7 platform.

Before start,  you can find How to install Oracle 11gR2 on Windows 7 using Wmware video tutorial  here

First we need to download deinstall tool from oracle site. For tools please click here.

Click See All for the related platform for which you want to download the Deinstallation Tool.

1. Unzip Deinstallation tool on your machine than follow below picture and open cmd session

2. set your Oracle 11gR2 home and than use below syntax:

C:\Windows\system32>d:

D:\>cd download\database\windows\deinstall

D:\>set ORACLE_HOME= D:\oracle\product\11.2.0\client_1

D:\>deinstall -home D:\oracle\product\11.2.0\client_1


#### ORACLE DEINSTALL & DECONFIG TOOL START#####
######## CHECK OPERATION START #######
Install check configuration START

Checking for existence of the Oracle home location D:\product\11.1.0\client_2
Oracle Home type selected for de-install is: CLIENT
Oracle Base selected for de-install is: null
Checking for existence of central inventory location C:\Program Files\Oracle\Inventory

Install check configuration END

Checking Windows and .NET products configuration START

The following Windows and .NET products will be deconfigured from the Oracle home : null

Checking Windows and .NET products configuration END

Network Configuration check config START

Network de-configuration trace file location: D:\download\database\windows\deinstall\logs\netdc_check46301.log

Network Configuration check config END

###### CHECK OPERATION END #######
#### CHECK OPERATION SUMMARY #######

Oracle Home selected for de-install is: D:\product\11.1.0\client_2
Inventory Location where the Oracle home registered is: C:\Program Files\Oracle\Inventory
The following Windows and .NET products will be deconfigured from the Oracle home : null
Do you want to continue (y – yes, n – no)? [n]: y

A log of this session will be written to: ‘D:\download\database\windows\deinstall\\logs\deinstall_deconfig2010-10-27_01-32-50-PM.out’
Any error messages from this session will be written to: ‘D:\download\database\windows\deinstall\\logs\deinstall_deconfig2010-10-27_01-32-50-PM.err’

###### CLEAN OPERATION START #######

Network Configuration clean config START

Network de-configuration trace file location: D:\download\database\windows\deinstall\logs\netdc_clean46302.log

The network configuration has been cleaned up successfully.

Network Configuration clean config END

Removing Windows and .NET products configuration START

Removing Windows and .NET products configuration END
Oracle Universal Installer clean START

Detach Oracle home ‘D:\product\11.1.0\client_2’ from the central inventory on the local node : Done

Failed to delete the file ‘D:\product\11.1.0\client_2\inventory\invDetails.properties’. The file is in use.
Failed to delete the directory ‘D:\product\11.1.0\client_2\inventory’. The directory is not empty.
Failed to delete the file ‘D:\product\11.1.0\client_2\oci.dll’. The file is in use.
Failed to delete the directory ‘D:\product\11.1.0\client_2’. The directory is no t empty.
Delete directory ‘D:\product\11.1.0\client_2’ on the local node : Failed <<<<

Delete directory ‘C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Oracle OraClient11g_home2’ on the local node : Done

Removing oracle home ‘D:\product\11.1.0\client_2’ from PATH variable on the local node : Done

Delete directory ‘C:\Program Files\Oracle\Inventory’ on the local node : Done

Delete directory ‘C:\Program Files\Oracle’ on the local node : Done

Delete Registry key ‘HKEY_LOCAL_MACHINE\Software\Oracle\inst_loc’ on the local node : Done

Oracle Universal Installer cleanup was successful.

Oracle Universal Installer clean END

Oracle install clean START

Oracle install clean END

Moved default properties file D:\download\database\windows\deinstall\response\deinstall_OraClient11g_home2.rsp as D:\download\database\windows\deinstall\respons
e\deinstall_OraClient11g_home2.rsp0

##### CLEAN OPERATION END ######
#### CLEAN OPERATION SUMMARY ######

Successfully detached Oracle home ‘D:\product\11.1.0\client_2’ from the central inventory on the local node.
Failed to delete directory ‘D:\product\11.1.0\client_2’ on the local node.
Successfully deleted directory ‘C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Oracle – OraClient11g_home2’ on the local node.
Successfully removed oracle home ‘D:\product\11.1.0\client_2’ from PATH variable on the local node.
Successfully deleted directory ‘C:\Program Files\Oracle\Inventory’ on the local node.
Successfully deleted directory ‘C:\Program Files\Oracle’ on the local node.
Successfully deleted Registry key ‘HKEY_LOCAL_MACHINE\Software\Oracle\inst_loc’ on the local node.
Oracle Universal Installer cleanup was successful.

Oracle install successfully cleaned up the temporary directories.
##########################
### ORACLE DEINSTALL & DECONFIG TOOL END ####

D:\download\database\windows\deinstall>


Reference:

http://download.oracle.com/docs/cd/E11882_01/install.112/e10843/deinstall.htm#CIHDGGJJ

############ ORACLE DEINSTALL & DECONFIG TOOL START #################################### CHECK OPERATION START ########################
Install check configuration START

Checking for existence of the Oracle home location D:\product\11.1.0\client_2
Oracle Home type selected for de-install is: CLIENT
Oracle Base selected for de-install is: null
Checking for existence of central inventory location C:\Program Files\Oracle\Inv
entory

Install check configuration END

Checking Windows and .NET products configuration START

The following Windows and .NET products will be deconfigured from the Oracle hom
e : null

Checking Windows and .NET products configuration END

Network Configuration check config START

Network de-configuration trace file location: D:\download\database\windows\deins
tall\logs\netdc_check46301.log

Network Configuration check config END

######################### CHECK OPERATION END #########################

####################### CHECK OPERATION SUMMARY #######################
Oracle Home selected for de-install is: D:\product\11.1.0\client_2
Inventory Location where the Oracle home registered is: C:\Program Files\Oracle\
Inventory
The following Windows and .NET products will be deconfigured from the Oracle hom
e : null
Do you want to continue (y – yes, n – no)? [n]: y
A log of this session will be written to: ‘D:\download\database\windows\deinstal
l\\logs\deinstall_deconfig2010-10-27_01-32-50-PM.out’
Any error messages from this session will be written to: ‘D:\download\database\w
indows\deinstall\\logs\deinstall_deconfig2010-10-27_01-32-50-PM.err’

######################## CLEAN OPERATION START ########################

Network Configuration clean config START

Network de-configuration trace file location: D:\download\database\windows\deins
tall\logs\netdc_clean46302.log

The network configuration has been cleaned up successfully.

Network Configuration clean config END

Removing Windows and .NET products configuration START

Removing Windows and .NET products configuration END
Oracle Universal Installer clean START

Detach Oracle home ‘D:\product\11.1.0\client_2’ from the central inventory on th
e local node : Done

Failed to delete the file ‘D:\product\11.1.0\client_2\inventory\invDetails.prope
rties’. The file is in use.
Failed to delete the directory ‘D:\product\11.1.0\client_2\inventory’. The direc
tory is not empty.
Failed to delete the file ‘D:\product\11.1.0\client_2\oci.dll’. The file is in u
se.
Failed to delete the directory ‘D:\product\11.1.0\client_2’. The directory is no
t empty.
Delete directory ‘D:\product\11.1.0\client_2’ on the local node : Failed <<<<

Delete directory ‘C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Oracle –
OraClient11g_home2’ on the local node : Done

Removing oracle home ‘D:\product\11.1.0\client_2’ from PATH variable on the loca
l node : Done

Delete directory ‘C:\Program Files\Oracle\Inventory’ on the local node : Done

Delete directory ‘C:\Program Files\Oracle’ on the local node : Done

Delete Registry key ‘HKEY_LOCAL_MACHINE\Software\Oracle\inst_loc’ on the local n
ode : Done

Oracle Universal Installer cleanup was successful.

Oracle Universal Installer clean END

Oracle install clean START

Oracle install clean END

Moved default properties file D:\download\database\windows\deinstall\response\de
install_OraClient11g_home2.rsp as D:\download\database\windows\deinstall\respons
e\deinstall_OraClient11g_home2.rsp0

######################### CLEAN OPERATION END #########################

####################### CLEAN OPERATION SUMMARY #######################
Successfully detached Oracle home ‘D:\product\11.1.0\client_2’ from the central
inventory on the local node.
Failed to delete directory ‘D:\product\11.1.0\client_2’ on the local node.
Successfully deleted directory ‘C:\ProgramData\Microsoft\Windows\Start Menu\Prog
rams\Oracle – OraClient11g_home2’ on the local node.
Successfully removed oracle home ‘D:\product\11.1.0\client_2’ from PATH variable
on the local node.
Successfully deleted directory ‘C:\Program Files\Oracle\Inventory’ on the local
node.
Successfully deleted directory ‘C:\Program Files\Oracle’ on the local node.
Successfully deleted Registry key ‘HKEY_LOCAL_MACHINE\Software\Oracle\inst_loc’
on the local node.
Oracle Universal Installer cleanup was successful.

Oracle install successfully cleaned up the temporary directories.
#######################################################################

############# ORACLE DEINSTALL & DECONFIG TOOL END #############

D:\download\database\windows\deinstall>