Plz follow progress belowed step by step, you will uninstall oracle sucessfully:
1、程序(All Programs) -- Oracle-OraClient10g_home1/2 -- Oracle Installation Products -- Uninversal install -- Deinstall Products
2、start -- Run -- regedit --
HKEY_CURRENT_USER -- Software -- delete Oracle
HKEY_LOCAL_MACHINE -- SOFTWARE -- delete Oracle
HKEY_LOCAL_MACHINE -- SYSTEM -- CurrentControlSet -- Services -- delete Oracle
3、delete oracle directory, eg. c:\oracle
删除oracle在安装时默认生成的目录，一般在c盘下。
4、delete oracle Path of environment variable
My computer -- Properties -- Advanced -- Environment Variables -- Path
delete all the paths which including ‘oracle‘，
我的电脑 -- 属性 -- 高级 -- 环境变量 -- Path
删除里面含有oracle的路径
5、delete ORACLE_HOME if exist（删除ORACLE_HOME ）
6、After restarted, delete the installational directory of oracle
重启后，删除安装oracle的目录，如：d:\oracle
原文：https://www.cnblogs.com/jijm123/p/12285130.html