How to fix the compile time warning "No way to resolve conflict between mscorlib, Version=4.0.0.0"?

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Dear Xamarin Pros,

Please help.

How to fix the compile time warning "No way to resolve conflict between mscorlib, Version=4.0.0.0"?

I have a brand new install of Visual Studio 2017 on Windows 10, and created a brand new Xamarin Forms project, and I get the following compile-time warning...

No way to resolve conflict between "mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" and "mscorlib, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e". Choosing "mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" arbitrarily.

...and I like to treat warnings as errors when I can, so how can fix this warning?

Please advise.

Thanks.

-- Mark Kamoski

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