Error: Could not install …
Error: Value cannot be null.
Parameter name: key
Usage: new options
…
When building a new solution template for ASP.NET Core solution, I received the above error. I had not seen this with prior template build efforts. This was new with .NET Core.
The error occurs when one of the node_modules folders contain a template.json file. The solution for me, was to entirely remove the node_modules directory before attempting to build the template.
Reference: https://github.com/dotnet/cli/issues/8989
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dotnet new–install Error
When building a new solution template for ASP.NET Core solution, I received the above error. I had not seen this with prior template build efforts. This was new with .NET Core. - October 1, 2018