Deinstall the Oracle database Software manually from window Server
Steps to uninstall or manually delete the Oracle DB software from windows server:
1. Delete the Oracle_home folder. (check the PATH from services.msc by right click Properties)
2. Delete the Oradata folder. (Delete all the Datafiles location)
3. Delete the Oracle inventory folder. C:\Program Files\Oracle\Inventory
4.Open REGEDIT and delete services present in services.msc
Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
Look for Oracle Services and delete them.
5. In REGEDIT and Delete the Oracle home entry
DONOT DELETE COMPLETE ORACLE FOLDER complete, it may contain ORACLE OTHER SOFTWARE.
In my case i am having ORACLE Virtual box installed on my machine.So, i only delete key_oraDB9Home1 at location: Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Oracle
6. In REGEDIT, Delete any Oracle ODBC entries. Go to HKEY_LOCAL_MACHINE\SOFTWARE\ODBC.
7. In REGEDIT, Delete the Event log entries related to Oracle.
Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\Application
8. Exit Regedit.
9. Go to reset the Environment Variable “PATH”. Delete Oracle Software entry from PATH Variable.
Start > Control Panel > System > Environment tab OR Search environment variable.
Now remove from the environment variable.
10. Delete Oracle entries from Startup Menu of Windows. ProgramDATA is hidden folder
Location PATH: %ProgramData%/Microsoft/Windows/Start Menu/Programs.
Example: C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Oracle-OraDB19Home1
Note: If not find then open startup menu and go to item and right click on it and go to location.
11. Remove Oracle Group created during installation from windows.
Open lusrmgr.msc –> open Local Users and Groups” window –> Go to Groups and delete all related to Oracle Started with ORA_
12. Finish the uninstalled process of Oracle.