https://download.microsoft.com/download/b/7/8/b78da045-4d6c-42b2-ae79-244b773b4a83/NDP45-DevPack-KB2899999-x86.exe
Before installing, you can verify your current version via the : Open regedit.exe . net framework 45 developer pack link
Unlike the "Runtime" version, which only allows a machine to apps, the Developer Pack includes: The Runtime : Core files needed to execute applications. Multi-Targeting Pack https://download
Direct link to the Developer Pack (exact file): https://download.microsoft.com/download/E/2/1/E21644B5-2DF2-47C2-91BD-63C560427900/NDP45-DevPack-KB296829-x86-x64-ENU.exe net framework 45 developer pack link
After installation, check:
Microsoft officially hosts the Developer Pack on their servers. You can grab it directly below: