When is Microsoft .NET Framework 3.5 SP1 end of life?

Microsoft .NET Framework 3.5 SP1 reaches end of life on Jan 9, 2029 (in 2 years). After that it gets no more updates, including security fixes.

When was Microsoft .NET Framework 3.5 SP1 released?

Microsoft .NET Framework 3.5 SP1 was released on Nov 19, 2007.

Run reg query "HKLM\SOFTWARE\Microsoft\Net Framework Setup\NDP" /s, then paste the result into the “Am I up to date?” box on this page.

Supported until Jan 9, 2029

Yes

Microsoft .NET Framework 3.5 SP1 is supported until Jan 9, 2029 (in 2 years).

Supported Today What “supported” means

Is Microsoft .NET Framework 3.5 SP1 still supported?: Yes. Microsoft .NET Framework 3.5 SP1 is supported until Jan 9, 2029 (in 2 years).
When is Microsoft .NET Framework 3.5 SP1 end of life?: Microsoft .NET Framework 3.5 SP1 reaches end of life on Jan 9, 2029 (in 2 years). After that it gets no more updates, including security fixes.
When was Microsoft .NET Framework 3.5 SP1 released?: Microsoft .NET Framework 3.5 SP1 was released on Nov 19, 2007.
How do I check which Microsoft .NET Framework version I have?: Run reg query "HKLM\SOFTWARE\Microsoft\Net Framework Setup\NDP" /s, then paste the result into the “Am I up to date?” box on this page.

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