REPLACE-CALC.BAT

@echo off
rem REPLACE-CALC.BAT
rem
rem Replace the default Windows calculator (calc.exe) with
rem Moffset Freecalc (http://www.moffsoft.com/freecalc.htm)
rem
rem Windows 10's calculator has a terrible UI.  Moffset's is free,
rem and while not beautiful, is much more usable.
rem
rem The batch commands below use debbugger routines in the registry as noted here:
rem
rem https://stackoverflow.com/questions/2984846/set-image-file-execution-options-will-always-open-the-named-exe-file-as-defaul
rem
rem Note that a different calculator could easily be used instead by changing
rem the "\Moffset Freecalc\MoffFreeCalc.exe" below to something else.
rem
rem The Image File Execution debugger technique used here could be used to
rem replace other Windows built-in apps as well.  (E.g., Notepad++
rem replacing notepad.exe.)
rem
rem by Matthew Borcherding
rem matt@borchtech.com
rem updated 10-06-2018

   setlocal

rem
rem Check if on a 64-bit OS.  Setup program files directory accordingly.
rem

   set pf=%programfiles%
   if %PROCESSOR_ARCHITECTURE%==AMD64 set pf=%programfiles(x86)%

rem
rem The %pf% variable is now set to the "%programfiles%" directory
rem on 32-bit systems, and the "%programfiles(x86)%" directory
rem on 64-bit systems,
rem

rem
rem Now double-check that Moffset FreeCalc is installed.
rem No point to do this if it's not already installed.
rem

   if not exist "%pf%\Moffsoft FreeCalc\MoffFreeCalc.exe" goto end

rem
rem OK, Freecalc is installed.  Let's set the proper registry keys.
rem

   reg add "HKLM\Software\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\calc.exe" /v "Debugger" /t REG_SZ /d "%pf%\Moffsoft FreeCalc\MoffFreeCalc.exe" /f


:end
rem
rem Done!
rem