Check for .NET4.5+ with NSIS

Question

All, I am aware of the following methods to check the framework version in NSIS. For .NET4.0+ I currently use

Function IsDotNetInstalled

    StrCpy $0 "0"
    StrCpy $1 "SOFTWARE\Microsoft\.NETFramework" ; Registry entry to look in.
    StrCpy $2 0

    StartEnum:
    ; Enumerate the versions installed.
    EnumRegKey $3 HKLM "$1\policy" $2

    ; If we don't find any versions installed, it's not here.
    StrCmp $3 "" noDotNet notEmpty

    ; We found something.
    notEmpty:
        ; Find out if the RegKey starts with 'v'.  
        ; If it doesn't, goto the next key.
        StrCpy $4 $3 1 0
        StrCmp $4 "v" +1 goNext
        StrCpy $4 $3 1 1

        ; It starts with 'v'.  Now check to see how the installed major version
        ; relates to our required major version.
        ; If it's equal check the minor version, if it's greater, 
        ; we found a good RegKey.
        IntCmp $4 ${DOT_MAJOR} +1 goNext yesDotNetReg
        ; Check the minor version.  If it's equal or greater to our requested 
        ; version then we're good.
        StrCpy $4 $3 1 3
        IntCmp $4 ${DOT_MINOR} yesDotNetReg goNext yesDotNetReg

    goNext:
        ; Go to the next RegKey.
        IntOp $2 $2 + 1
        goto StartEnum

    yesDotNetReg:
        ; Now that we've found a good RegKey, let's make sure it's actually
        ; installed by getting the install path and checking to see if the 
        ; mscorlib.dll exists.
        EnumRegValue $2 HKLM "$1\policy\$3" 0
        ; $2 should equal whatever comes after the major and minor versions 
        ; (ie, v1.1.4322)
        StrCmp $2 "" noDotNet
        ReadRegStr $4 HKLM $1 "InstallRoot"
        ; Hopefully the install root isn't empty.
        StrCmp $4 "" noDotNet
        ; Build the actuall directory path to mscorlib.dll.
        StrCpy $4 "$4$3.$2\mscorlib.dll"
        IfFileExists $4 yesDotNet noDotNet

    noDotNet:
        ; No, something went wrong along the way.  Looks like the 
        ; proper .NET Framework isn't installed.  
        MessageBox MB_ICONEXCLAMATION "To install UserCost, Microsoft's .NET Framework v${DOT_MAJOR}.${DOT_MINOR} \
        (or higher) must be installed. Cannot proceed with the installation!"
        ${OpenURL} "${WWW_MS_DOTNET4}"
        Abort

    yesDotNet:
        ; Everything checks out. Proceed with the rest of the installation.

FunctionEnd

This works very well for .NET4.0, but I have now extended my application to utilise the async/await features and subsequently need users to install .NET4.5+. The above method is not suitable as the installation for .NET4.5 now does not use the regestry path 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft.NETFramework\Policy" to store any new information, that is that path does not seem to hold a value that changes between .NET4.0 and 4.5. Now I have seen the following posts:

NSIS Installer with .NET 4.5

which uses the registry path/entry 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP' to do the checks. Now this also does bot work as the entry does not change from .NET4.0 to 4.5. I notice that there is and entry called 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft.NETFramework\v4.0.30319\SKUs.NETFramework,Version=v4.5' can I use this to check the Framework version invariably?

Is there an offical line of the way to check for .NET4.5 using NSIS?

Thanks for your time.

---

Note: subsequently some installation of .NET4.5 my users have performed have had registry values for

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full 

a DWORD value named Release was not 378389 but 378181. Making this change seemed to resolve the problem as the entry for the Release is not in the registry for .NET4.5 and below.

Answer 1

Yes there is an official way to check if .NET Framework 4.5 is installed, even if it's not really friendly. From MSDN:

You can test whether the .NET Framework 4.5 or the .NET Framework 4 is installed by checking the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full subkey in the registry for a DWORD value named Release. The existence of this DWORD indicates that the .NET Framework 4.5 has been installed on that computer. The value of Release is a version number. To determine if the final release version of the .NET Framework 4.5 is installed, check for a value that is equal to or greater than 378389.

http://msdn.microsoft.com/en-us/library/hh925568.aspx

It means you first have to check if 4.0 is installed and then to check if there is a value named Release in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full, if so then 4.5 is already installed (I think you can skip the check for a pre-release version).

EDIT: check this post here on SO for details about detecting older installed .NET versions and this MSDN article to distinguish between for 4.5.x versions.