Nuget and "Unable to load the service index" [duplicate]

Question

I'm having a trouble with Monodevelop. I'm using LinuxMint Serena (18.1) and Monodevelop 7.0.1 (build 24). When trying to add nuget package on a new project, I get the next answer:

[nuget.org] Unable to load the service index for source https://api.nuget.org/v3/index.json. An error occurred while sending the request
Error: SecureChannelFailure (Object reference not set an instance of an object) Object reference not set to an instance of an object

I check the api nuget address and is normal, nothing strange about the link. I tried to copy the old package from the original Visual Studio project but remain the problem.

Thanks in advance.

EDIT: After trying many things with no success, I use the old nuget packages downloaded from the old Visual Studio project. I don't know if making that works or the fact that I take the project and open it up with Monodevelop for Windows fixed the issue.

Answer 1

I have the same question in ubuntu(16.04) Monodevelop(7.0.1). I can access to http://api.nuget.org/v3/index.json in my browser, but when I add nuget package in monodevelop, it throw the exception, " Unable to load the service index for source https://api.nuget.org/v3/index.json". I solve this problem by checking the updater, check and install all software updates. You can try it. Good luck!