【解决办法】：
正常情况下，运行 ArcGIS for Desktop 光盘中的 “冲突检测”工具，会自动完全卸载低版本的ArcGIS 程序。如果遇到异常无法卸载（例如安装过非正式版软件），如下位置是ArcGIS程序会使用到的位置，请尝试手动清空，有些文件夹是隐藏文件夹，设置显示出来然后删除。
文件夹:
C:Program Files (x86)ArcGIS
C:Program Files (x86)Esri
C:Program Files (x86)Common FilesArcGIS
C:Program Files (x86)Common FilesEsri
C:Program FilesArcGIS
C:Program FilesEsri
C:Program FilesCommon FilesArcGIS
C:Program FilesCommon FilesEsri
C:Program DataEsri
C:Program DataArcGIS
C:Program DataFLEXnet
C:Users<USERNAME>AppDataLocalESRI
C:Users<USERNAME>AppDataLocalArcGIS
C:Users<USERNAME>AppDataRoamingESRI
C:Users<USERNAME>AppDataRoamingArcGIS
C:ProgramDataMicrosoftWindowsStart MenuProgramsArcGIS
C:ProgramDataMicrosoftWindowsStart MenuProgramsEsri
注册表：
HKEY_LOCAL_MACHINESOFTWAREESRI
HKEY_LOCAL_MACHINESOFTWAREWow6432NodeESRI
HKEY_LOCAL_MACHINESOFTWAREWow6432NodeFlex LM License Manager
HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionUninstall<Delete Any Folder that contains ArcGIS or Esri>
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetservicesArcGIS Server
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetservices<Delete Any Folder that contains ArcGIS or Esri within>
HKEY_LOCAL_MACHINESYSTEMCurrentControlSetservicesFLEXnet Licensing Service
HKEY_CLASSES_ROOTInstallerProducts<Delete Any Folder that contains ArcGIS or Esri within>
HKEY_CLASSES_ROOTInstallerAssemblies<Delete Any Folder that contains ArcGIS or Esri within>
HKEY_CLASSES_ROOT<Delete and Folder that contains ArcGIS or Esri within>
HKEY_CLASSES_ROOTInstallerAssembliesGlobal<Delete all Keys beginning with ESRI or ArcGIS>
安全设置：
Security Settings -> Local Policies -> Security Options
Locate User Account Control: Run all administrators in Admin Approval and change the setting from Enabled to Disabled
Uninstall: C:WindowsassemblyEsri.* (This can be hundreds of files)
Uninstall: C:WindowsassemblyArcGIS.* (This can be hundreds of files)