Missing System.Net.Http after upgrading Visual Studio to 15.5

7
votes

We've got an existing solution consisting of an ASP.NET MVC project and a bunch of libraries, all of the projects are targeting .NET 4.6.1.

After upgrading Visual Studio from 15.3 to 15.5 I get a few compile errors stating that it can't find the System.Net.Http assembly.

The type 'HttpResponseMessage' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Net.Http, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

I read the release notes but I could not find anything that would cause this issue. Why would upgrading Visual Studio from 15.3 to 15.5 result in these errors?

2
c#.netasp.net-mvcvisual-studio-2017dotnet-httpclient

2 Answers

1
votes

I guess your issue is related to what is written here https://developercommunity.visualstudio.com/content/problem/160241/errors-reported-when-none-exist.html because it appears this is all about project references. Please see if the proposed solution there

Uncheck option "Allow parallel project initialization"

helps you as well.

By the way, it is worth mentioning that 15.5 updated apparently brought up other serious issues to existing projects as written here https://developercommunity.visualstudio.com/content/problem/160609/vb-option-strict-on-warnings-are-shown-on-existing.html

I hope all this helps to solve your issue or to investigate on it deeper, at least.

0
votes

Try updating the System.Net.Http nuget to make sure that you have the latest version