"Recaptcha.Web" built against ".NETFramework,Version=v4.5" framework

[Echeban]

I have a complex project using .NETFramework,Version=v4.0 which I cannot migrate to .NET 4.5 because that requires VS 2012 or higher which I do not have, I only have VS 2010.

I just want to upgrade my ASP project to reCaptchaV2
I get this error:

The primary reference "Recaptcha.Web" could not be resolved because it was built against the ".NETFramework,Version=v4.5" framework. This is a higher version than the currently targeted framework ".NETFramework,Version=v4.0".

What can I do to resolve this issue?
Is there a version of Recaptcha.Web targeted at 4.0 or lower that I can use, please!

[tanveery]

@Echeban reCAPTCHA for .NET 3 is coming up. Support for .NET 4, 4.6, 4.7 and .NET Core will be added.

[F0b0s]

@tanveery I would like to collaborate with you in reCAPTCHA for .NET 3 project. Can i send a PR?