Uninstall Oracle Manually
October 10, 2011 40 Comments
1.Uninstall all Oracle components using the Oracle Universal Installer (OUI).
2.Run regedit.exe and delete the HKEY_LOCAL_MACHINE/SOFTWARE/ORACLE. This contains registry entires for all Oracle products. 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 obvious which ones relate to Oracle.
3.Reboot your machine.
4.Delete the “C:\Oracle” directory, or whatever directory is your ORACLE_BASE.
5.Delete the “C:\Program Files\Oracle” directory.
6.Empty the contents of your “c:\temp” directory.
7.Empty your recycle bin.
About Mariami Kupatadze
DBA Knowledge Base 
Very nice. we can do manually by doing above steps.. Can you tell me steps for installing oracle manually?
Please, provide me with the following information and will try to help you.
1. On what OS do you install Oracle?
2. What version of Oracle do you want to install?
As I can guess you want to install standalone instance not Standby or RAC yes?
I have windows 7 32-bit… I want to install ora 10g on my machine…
You can download 10g installation from here.. https://edelivery.oracle.com/EPD/Search/handle_go
You will need registration if you are not registered yet.
For example, download 10.2.0.1.0 version.
Download both parts: Part 1 of 2 and Part 2 of 2
Extract Part 1 of 2. It should be extracted into “database” folder. After that extract Part 2 of 2 , this should also be extracted in “database” folder..(So both parts’ contents are collected in one folder)
Run: setup.exe and follow the instruction.
You are trying to say. We can also uninstalled by Regedit? But it’s a os and if we deleted directly from there so it’s deleted smoothly? On second time it will not creating a problem? But if i asked you Which one installation is good? Manually or Doing OUI.?
No uninstallation happens not just by regedit, first of all you are using OUI (1st step)
After doing just first step oracle lefts its folders and entries in regedit. Which means that OUI lefts some junks in our computer, that should be cleaned that’s why there exists the other steps.
Sorry, I don’t remember what problems may exist if you don’t follow 2-7 steps.
I will try on my test environment and write you the answer later…
What about the installation , my opinion is to use OUI. Because it is simpler and I think satisfies all the requirements needed for to install oracle software smoothly.
Thank you for your comment.
When i am trying to install a Oracle 10 g again. it’s coping in two drive. In one drive it’es showing oracle data which are store.
N second drive store database. Is this possible? or some thing wrong in this?
if oradata file is stored in separate place other than database software itself , it is the best practice .. This system will be more protected than everything on the same place. Nothing is bad. If you don’t want it, you can move datafiles after install, so
no problem.
Actually i was install in my external hard disk. When i am going to removing. It’s can’t remove shown some comments. This drive is or this file is using some one. why it’s showing this. Why i can’t remove smoothly. For this reason i again installed in internal drive so it’s shown your database is store in external drive.. Tell me simple way. Which option i select? Uninstall n installed again or it’s OK. Why external drive didn’t remove without showing any comments.?
No, it is not OK. You should not install oracle on external drives.. You should uninstall and install oracle again in internal drives.. if you need your external drive now, just shutdown database and try to safetly remove drive.. if you have problems again then go to the windows services and stop all services starting or containing word “oracle”, then if you want your oracle up.. connect your external drive start all services you shutdown and startup the instance.. BUT is is better to uninstall oracle from external drive
OK. That means it’s a wrong way i installed? OK. Thanks. It’s help me lot….
My friend has window 7 64-bit. So lower bit version ora10g 32-bit. Does not installed? or it does?
Yes you can install.. But indicate compatibility .Or after you run “setup.exe” and clicking the “Next” button there may appear error message..just close it and choose “Reinstall using recommended settings” <-windows 7 will pop-up this window. After that you can continue installing…
yes. As you told i did exactly same. N good news is it’s installed successfully. Thanks.
Should i Installed RAC on my PC. Ora 10g already installed in my PC. We can keep both RAC and Ora10g? Or not?
Yes you can install Real Application Cluster and standalone server, but they must have different database names.
Installing 2-node RAC on linux is explained here: https://dba010.wordpress.com/2012/09/04/install-oracle-11g-rac-on-oracle-enterprise-linux-5/
I have tried on window 7. But it wasn’t installed.
Hey, R u there? I am waiting for your answer….. Thanks.
I need your help…..
I will try on my test environment and write you the answer later
Hi, Did you try it?
I did not yet, today I will do it for sure. But after asking with other colleges they said yes it is possible. What did you tried exactly? What errors appeared during your installation ? You know, first of all you should install grid before installing oracle database software.
I uninstalled ora 10g from in control panel to software. That means I didn’t uninstalled? While trying to installed again i can’t installed. So now i have to delete registry 1st? how it’will be deleted?
If %ORACLE_HOME% folder still exists , try to find Oracle Universal Installer (OUI). In my case it is C:\oracle\product\10.2.0\db_1\oui\bin\setup.exe. So if this OUI works fine then try to uninstall oracle by it pressing “Deinstall Products”->checking home option and clicking remove button then following my steps. If it fails, then close it and follow my steps from 2. I you have some trouble, please tell me.
Yes. After i will done. I will let you know.. Thanks.
I try in search option to find ORACLE_HOME. But i didn’t find it.
where did you searched in regedit or you were searching folder named ORACLE_HOME?
No.. In drive.. you mean i have to search in regedit?
No, I meant that %ORACLE_HOME% is a variable , that value is the complete path to the oracle database installation folder for me it is C:\oracle\product\10.2.0\db_1. So you should find the oracle installation path, you may have something like that: C:\app\oracle\product\10.2.0\db_1 or another, you should know. Try to find it
OK. IF i find it. Than i have to uninstall from OUI?
Yes , try if it doesn’t work, then try to follow my steps from 2.
Yes. I successfully uninstalled ora 10g. By followed your steps. Thanks for the help…
I uninstalled n again i installed it’s error comes. With SID is already used by this machine? Than means i didn’t uninstalled? Or else?
Yes it means oracle was not successfully uninstalled.
Yup so i have to delete all rededit entry first? N than i will installed again? Or some thing else?
Thanks for the help. it’s worked… Thanks again….
Error ora 12547.
R u there? It’s error related with that?
Hey Any this wrong i asked you?