uninstall or continue before install

...some code...

InstallDir "$PROGRAMFILES\somewhere\"

...some code...

Section -Post

  WriteUninstaller "$INSTDIR\uninstall.exe"

  WriteRegStr ${PRODUCT_UNINST_ROOT_KEY} "${PRODUCT_UNINST_KEY}" "DisplayName" "$(^Name)"

  WriteRegStr ${PRODUCT_UNINST_ROOT_KEY} "${PRODUCT_UNINST_KEY}" "UninstallString" "$INSTDIR\uninstall.exe"

SectionEnd



Function .onInit

ReadRegStr $R1 HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\${PRODUCT_NAME}" "UninstallString"

  StrCmp $R1 "" done

 

  MessageBox MB_YESNO|MB_ICONEXCLAMATION \

  "${PRODUCT_NAME} is already installed. $\n$\nDo you want to remove \

  the old installation before installing ${PRODUCT_NAME} ." \

  IDNO done

  

;Run the uninstaller

  ClearErrors

  ExecWait '$R1 _?=$INSTDIR'

done: 

FunctionEnd

Im installing application in different folder than InstallDir

Why when i run the installer ,and when he find that application is already installed uninstaller run from InstallDir instead from the place where application is already installed - $R1

if i add
ExecWait '$INSTDIR\uninstall.exe'
uninstaller is not found.

I guess im missing something ,but what 🙂

You're missing the fact that $INSTDIR is not yet initialized when running function .onInit

Thanks for the tips ,it all working fine now ,this post help me too

http://forums.winamp.com/showthread.php?postid=671288#post671288