NuGet.targets error : '.', hexadecimal value 0x00, is an invalid character after upgrade to .Net Core 2.1.1

Question

after upgrade to .Net Core 2.1.1 I got this error:

  C:\Program Files\dotnet\sdk\2.1.301\NuGet.targets(114,5): error : An error 
occurred while retrieving package metadata for 'System.IO.4.3.0' from source
     'C:\Program Files\dotnet\sdk\NuGetFallbackFolder'. 
    C:\Program Files\dotnet\sdk\2.1.301\NuGet.targets(114,5): error :   '.', 
hexadecimal value 0x00, is an invalid character. Line 1, position 1. 

not able to solve it using

nuget.exe locals -clear global-packages
nuget.exe locals -clear packages-cache
nuget.exe locals -clear http-cache

or

nuget.exe locals -clear all

thanks for any help

Answer 1

In my case it was simple, I just did the following:

• In Visual Studio, click: TOOLS > NUGET PACKAGE MANAGER > PACKAGE MANAGER SETTINGS
• Select Option NUGET PACKAGE MANAGER > GENERAL
• In General, click on button CLEAR ALL NUGET CACHE(S) await a few seconds
• After this , close all windows and go to TOOLS > NUGET PACKAGE MANAGER > PACKAGE MANAGER CONSOLE
• type dotnet restore
• done =)