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#include <windows.h>

bool IsDotNet45Installed()
{
    DWORD value{};
    DWORD dataSize = sizeof(value);
        
    const LONG retCode = ::RegGetValue(
        HKEY_LOCAL_MACHINE,
        L"SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\",
        L"Release",
        RRF_RT_REG_DWORD,
        nullptr,
        &value,
        &dataSize
    );

    if (retCode != ERROR_SUCCESS)
    {
        return false;
    }

    return value >= 378389;
}

if (releaseKey >= 528040)
return "4.8 or later";
if (releaseKey >= 461808)
return "4.7.2";
if (releaseKey >= 461308)
return "4.7.1";
if (releaseKey >= 460798)
return "4.7";
if (releaseKey >= 394802)
return "4.6.2";
if (releaseKey >= 394254)
return "4.6.1";
if (releaseKey >= 393295)
return "4.6";
if (releaseKey >= 379893)
return "4.5.2";
if (releaseKey >= 378675)
return "4.5.1";
if (releaseKey >= 378389)
return "4.5";
// This code should never execute. A non-null release key should mean
// that 4.5 or later is installed.
return "No 4.5 or later version detected";