To uninstall Oracle database on Windows, we have to delete the all the related Ora* registry keys, files and folders manually.

P.S Tested with Oracle database 19c on Windows 10

Note
I can’t find any uninstaller to uninstall the Oracle database automatically?

1. Stop Oracle* services

Press Windows key, type services, stop all Oracle related services.

Oracle services

2. Delete Oracle* registry keys

Press Windows key, type regedit, delete the following Windows registry keys if it exists. :

2.1 HKEY_LOCAL_MACHINE/SOFTWARE/Oracle*

Oracle registry keys

2.2 HKEY_LOCAL_MACHINE/SOFTWARE/Wow6432Node/Oracle* (64-bits Windows)

Oracle registry keys

2.3 HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Services/Oracle*

Oracle registry keys

Reboot Windows.

3. Delete Oracle* folders.

Delete the following Oracle* folders and files if it exists.

  • C:\Oracle or ORACLE_BASE
  • C:\Program Files\Oracle
  • C:\Program Files (x86)\Oracle
  • C:\ProgramData\Microsoft\Windows\Start Menu\Programs\ Oracle-related folders.
  • C:\Users Oracle-related folders.

Empty C:\temp and recycle bin.

Done. The Oracle database is uninstalled from the Windows completely.

References