TagHelpers version numbers

Ive been trying to develop a site in .net core MVC but have been getting a problem with TagHelpers and wonder if anyone might be able to suggest a solution

My site builds ok, but when I run it the web page displays the error

Cannot resolve TagHelper containing assembly 'Microsoft.AspNet.Mvc.TagHelpers'.
Error: Could not load file or assembly 'Microsoft.AspNet.Mvc.TagHelpers, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.

1.@addTagHelper "*, Microsoft.AspNet.Mvc.TagHelpers"

In the _ViewImports.cshtml page

I have checked and I have the NuGet package installed and TagHelpers declared in the program.json, as below. I have tried changing the TagHelpers to v1.0.0-rc2 which is what intelligence shows, but doing so produces and incompatable with the Mvc assembly then, changing that, causes others and so on and so on.

I have tried

1.@addTagHelper *, Microsoft.AspNet.Mvc.TagHelpers

(ie no brackets) in the _ViewImports.cshtml page anfd that doesnt help


The project.json contains:

"dependencies": {
"Microsoft.AspNetCore.Diagnostics": "1.0.0",
"Microsoft.AspNetCore.Mvc": "1.0.0",
"Microsoft.AspNetCore.Mvc.TagHelpers":"1.0.0",
"Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
"Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
"Microsoft.AspNetCore.StaticFiles": "1.0.0",
"Microsoft.EntityFrameworkCore": "1.0.0",
"Microsoft.EntityFrameworkCore.Design": {
"type": "build",
"version": "1.0.0-preview2-final"
},
"Microsoft.EntityFrameworkCore.SqlServer": "1.0.0",
"Microsoft.EntityFrameworkCore.Tools": {
"version":"1.0.0-preview2-final",
"type": "build"
},
"Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
"Microsoft.Extensions.Configuration.Json": "1.0.0",
"Microsoft.Extensions.Logging.Console": "1.0.0",
"Microsoft.NETCore.App": {
"version": "1.0.0",
"type": "platform"
}
},

"tools": {
"Microsoft.AspNetCore.Server.IISIntegration.Tools": {
"imports": "portable-net45+win8",
"version": "1.0.0"
},
"Microsoft.EntityFrameworkCore.Tools": {
"imports": "portable-net45+win8",
"version": "1.0.0"
}

},

"frameworks": {
"netcoreapp1.0": {
"imports": [
"dotnet5.6",
"portable-net45+win8"
]
}
},

If anyone can help I'd really appreciate it
Andy