Search code examples
windowsinstallationnsis

Installer didn't detect old installed version NSIS

I'am using NSIS to create a setup for my application and need to check if it's already installed:

 Name "${PRODUCT_NAME} ${PRODUCT_VERSION}"
    OutFile "MyAppInstaller.exe"
    InstallDir "$PROGRAMFILES\MyApp"
    InstallDirRegKey HKLM "${PRODUCT_DIR_REGKEY}" ""
    ShowInstDetails show
    ShowUnInstDetails show

    Function .onInit
    ; Check to see if already installed
      ReadRegStr $R0 HKLM "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_NAME} ${PRODUCT_VERSION}" "UninstallString"
      IfFileExists $R0 +1 NotInstalled
      Messagebox MB_ICONQUESTION|MB_YESNO "MyApp 1.0 is already installed.Do you want to uninstall old version"   IDNO Quit
         Exec $R0
    Quit:
      Quit


    NotInstalled:
      !insertmacro MUI_LANGDLL_DISPLAY

    FunctionEnd ...

but nothing happened it always proceed installation and didn't detect the old installed version, did I miss something? I don't know much about NSIS scripting so any help will be appreciated.

Solution

  • My only guess is that you are checking the wrong registry key or the returned path is quoted and/or has parameters so the file exists check fails.

    Verify the path with Messagebox mb_ok $R0 before the IfFileExists line and if it is empty you should try Process Monitor, it might be able to give you some clues...