VS 2017 [RESOLVED] The reference assemblies for framework ".NETFramework,Version=v4.6.1" were not found

My W10 laptop had a meltdown hence i have purchased a new one and now my 2017 project is producing an error i cannot rectify.

Quote:

Severity Code Description Project File Line Suppression State
Error The reference assemblies for framework ".NETFramework,Version=v4.6.1" were not found. To resolve this, install the SDK or Targeting Pack for this framework version or retarget your application to a version of the framework for which you have the SDK or Targeting Pack installed. Note that assemblies will be resolved from the Global Assembly Cache (GAC) and will be used in place of reference assemblies. Therefore your assembly may not be correctly targeted for the framework you intend. ProjectName

I cannot open the setting page in the My Project to change the target framework though i do have framework v4 Full in the list of the registry.;

Error on setting page:

Quote:

Could not resolve mscorlib for target framework '.NETFramework,Version=v4.6.1'. This can happen if the target framework is not installed or if the framework moniker is incorrectly formatted.

I have tried to manually edit the app.config file to various version as mention on some sites without any luck.

In "turn on windows features" i only have 3.5 which includes 2.0 and 3.0 and 4.8 advanced services.

I tired downloading 4.6.1 but message says not suitable for your system.

What are my option to sort this out

thanks
mick