Project file is incomplete. Expected imports are missing

Question

After format my computer I reinstalled Vs 2017 V 15.6.3 and install ASP.Net Core SDK from Microsoft 2.1.4

But when I create new asp core application VS failed with e

Answer 1

After installing VS2019 I started to have the same error when opening existing .Net Core solutions in VS2017.
In Visual Studio Installer I've updated VS2017 to the latest version (15.9.11) and the problem disappeared.

Later after upgrading VS2019 to the latest release I started to have the same errors and had to upgrade VS2017 again.