installmaker wrote: I include Microsoft Visual C++ 2012 Update 4 Redistributable and Microsoft Visual C++ 2010 SP1 Redistributable in my install package. I am looking for some guidance on what conditions to use to make sure that they install when they need to install. I am currently using the existence of the following registry keys. Microsoft Visual C++ 2012 Update 4 Redistributable will install if this key does not exist. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{2F73A7B2-E50E-39A6-9ABC-EF89E4C62E36} Microsoft Visual C++ 2010 SP1 Redistributable will install if this key does not exist. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{F0C3E5D1-1ADE-321E-8167-68EF0DE699A5} I am under the assumption that these keys are unique to the redistributables and should only be there if they have been installed. I would like to know if this method is reasonable or if there are better ways to ensure they get installed when needed. Any insight or advice will be much appreciated. Cheers. Hi installmaker, You are correct,redistributables maintain unique registry key under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall.Since it is product code based keys you can trust those enough Thanks, Jenifer ... View more