vc_redist.x64 repair install versus regular install

We've hit a number of issues lately where user's systems had back-level version of msvcp140.dll. This caused no end of grief.

I thought I'd change our install script to do this:

Section "Visual Studio Runtime"
SetOutPath "$INSTDIR"
File "..\x64\Release\vc_redist.x64.exe"
SetRegView 64
ReadRegDWORD $0 HKLM "Software\WOW6432Node\Microsoft\VisualStudio\14.0\VC\Runtimes\X64" "Bld"
SetRegView 32
${If} $0 != 33816
#
# vc_redist build 33816 isn't installed, so install it
#
ExecWait "$INSTDIR\vc_redist.x64.exe /install /passive /norestart"
${Else}
#
# vc_redist build 33816 is installed, force a repair install
#
ExecWait "$INSTDIR\vc_redist.x64.exe /repair /passive /norestart"
${Endif}

Delete "$INSTDIR\vc_redist.x64.exe"
SectionEnd

This sort of works if the 14.40.33816 build has never been installed, in which case it does a regular install, otherwise a repair is done.

However if the redist package has previously been installed and then uninstalled, the registry keys remain so it always does a repair install

So will a repair install do everything a regular install would but without checking that the redist has been installed?

Or do I need a better check for the vc_redist.x64 being installed or not?

Thanks
David

Any help much appreciated.

Most of the time, a repair install will refresh the application by re-installing the app in the background. Occasionally, the repair install will only examine the files and replace or repair what is necessary. In my experience, the repair installers usually just re-install the app, rather than the second more complicated option.

But this is Microsoft, they may write the more complicated installer.

However, checking the file dates on my last .NET repair install, the installer overwrote all of the files, suggesting a complete re-install of the package.

I think you will be all right if it just runs the repair install. The installer will see that the app is no longer installed and put everything back where it should be.

This is one thing that I don't like about some of MS's uninstall process. It eaves remnants in the registry. Without using a registry cleaner of some kind, or a brute force uninstaller that will clear remnants and leftovers, you can wind up with issues like this.

Best of luck.

We check these two registry keys:


One or both will contain a Version value, with a format such as 14.40.33810. You seem to be writing a Nullsoft (NSIS) installer, which does have a VersionCompare function you could use to compare against the known version number you're installing.