The details of the steps are as followed:
Step 1: Download VS 2017 from Microsoft website
Step 2: Open solution within vs 2017, you will be told once this happens, you can no longer open the project within vs 2015, however they do backup automatically a version at 2015
step 3: The xproj file at the heart of the application is transformed into a csproj file. This filetype is *now* editable by right clicking on the Main project heart within the directory, and selecting edit {!ProjectName}.csproj, it should open an XML file format.
step 4. Add these lines to the project. (Please note, the project may contain some of these lines already).Some has to add the runtimeidentifiers and supperdocker targets to a property group that already existed.
step 5. Open the project within the command prompt in the usual method (where you right click the project name, open file explorer at the project location and then crtl+shift clicking within the file explorer and selecting the open with command prompt option.
Step 6. Run: dotnet publish -c Release -r win7-x64 within the command prompt
NOTE: Please run the following command: npm install -g bower - within the nugget package manager console, this is meant to install bower globally or something along those lines. This process will publish a self-contained application of your project within the root directory>Bin>Release>Win64>publish
The command prompt should inform you of the location
That is how the latest and most prevalent 502.5 error that occurs with the 2015 --> 2017 upgrade is rectified.
Please do not forget to add the following lines:
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>netcoreapp1.1</TargetFramework>
<PreserveCompilationContext>true</PreserveCompilationContext>
<RuntimeIdentifiers>win7-x64;win7-x86;ubuntu.16.04-x64;</RuntimeIdentifiers>
<SuppressDockerTargets>True</SuppressDockerTargets>
</PropertyGroup>