.NET Framework 4.5 is supported on following:
A. Client OS:
- Windows 8 (32-bit and 64-bit editions)
- Windows 7 (32-bit and 64-bit editions)
- Windows Vista SP2 (32-bit and 64-bit editions)
B. Server OS:
- Windows Server 2012 (64-bit edition)
- Windows Server 2008 R2 (64-bit edition)
- Windows Server 2008 SP2 (32-bit and 64-bit editions)
Here, refer details:
MSDN: .NET Framework System Requirements[
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