The RPA installation guide provided in the PDN architect essentials course misses out on a few steps. Instead of installing RPA directly, first you have to set up the VS 2015 environment.
This can be done by launching the OpenSpanStudioVS2015Setup.exe
Note the .exe in the end. If you launch the .msi file, it will not work and you will get the error mentioned by the OP. Check the image I have embedded with this post. Launch only that file. It will install the VS shell and only after that will proceed to install RPA and this time it will get installed without any error.
The installation guide provided in the Related Content of the Pega Academy course (an updated attached with post) states to run the setup.exe. The setup installs the VS Shell, any missing, necessary components, and Pega Robotic Automation Studio. If you cannot find the exe file, please change the viewing properties of the Windows Explorer to see the file extensions to select the correct file.
Please note the course also states to contact support for acquiring the Plug-in version of the Pega Robotic Automation Studio if you have already installed a full version of Visual Studio 2015 on the laptop or VM.
Off course you would need to have admin rights on the machine and have Windows 10 installation media or image.
2. After installing .NET Framework 3.5, you have to enable it by going to “Control Panel \ Programs and Features \ Turn Windows Features On or Off" Select .NET Framework 3.5 then OK. Please see Screenshot 1-"Turn Windows Features On or Off"
3. Now, run “OpenSpanStudioVS2015Setup” Application - (as indicated in an earlier comment on this page), which is the Pre-requisites Wizard to install all the components in the correct order. Select all the pre-requisited components as indicated in Screenshot 2 - "Select All Components".