VS2015 - NuGet Install-Package : Invalid length for a Base-64 char array or string

Question

Something has gone catastrophically wrong with NuGet in my install of VS2015. Whenever I attempt to run Install-Package, I get the following error:

Install-Package : Invalid length for a Base-64 char array or string.
At line:1 char:1
+ Install-Package log4net
+ ~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception
    + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.Install 
   PackageCommand

I can't for the life of me find any other information about this issue. I have restarted VS, restarted my PC, tried re-installing NuGet, but I feel like this is an underlying issue with powershell.

Any suggestions would be greatly appreciated.

EDIT - SOLVED

So, after a frustrating evening, I have finally solved the issue. I had to uninstall VS2015, re-install it, clear my vssettings file then delete the NuGet.config file.

Answer 1

Cannot guarantee that this will work but according to https://github.com/NuGet/Home/issues/2239#issuecomment-193208925 the only thing you need to do is delete the nuget.config file. Sorry if it doesn't work for you.