System environment: 1, operating system: Windows 2000 Server, Machine memory 128m2, Database: Oracle 8i R2 (8.1.6) for NT Enterprise 3. Installation Path: D: / Oracle Uninstall Steps: 1, Start -> Setting -> Control Panel -> Administrative Tools -> The service stops all Oracle services. 2, start-> program -> Oracle - orahome81-> Oracle Installation Products-> Universal Installer Uninstall All Oracle Products 3, running regedit, select HKEY_LOCAL_MACHINE / SOFTWARE / ORACLE, press Del to delete this entry. 4, running regedit, select HKEY_LOCAL_MACHINE / SYSTEM / CURRENTCONTROLSET / SERVICES, scroll this list, delete all Oracle entry 5, from the desktop, startup group, program menu, delete all groups and icons related to Oracle 6, restart After the computer, you can completely remove the directory 7 where Oracle is located, delete files related to Oracle, select Oracle's default directory C: / Oracle, delete this entry directory and all subdirectory, and from Windows 2000 Directory (generally C : / Winnt) Delete the following file Oracle.ini, ORADIM80.INI8, WIN.INI file If there is a tag section of [Oracle], delete this paragraph